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By A. Mitchell

An approximate phase diagram has been developed for the CaF2-CaC2 system, indicating a eutectic point at 1240°C, Ncac2 = 0.13, and no detectable solid solution in either phase. The liquidus line is shown to correspond to a simple c22- ion in solution. A thermo-chemical study of&apos; the reaction between carbon-saturated Ni-Ca alloys and CaC2-CaF2 liquids indicates that lhe Raoullian activity coefficient of CaC2 in dilute solution in Cap2 al 1500°C lies between 8 and 10. Some effects of the stabilily of Cap2-CaC2 solutions at high temperatures on electroslag remelting praclice are outlined. THE alkaline earth acetylides. MIIC2, have a reasonably high thermochemical stability at high temperature in the solid state,&apos; with the exception of magnesium, which forms an unstable acetylide at low temperatures (-500°C) and a carbide, Mg2C3, in the range 700&apos; to 1000°C. The acetylides of calcium and barium have been shown to have limited solubility in their respective chlorides,&apos; and further these solutions contain the acetylide as a C: ion.&apos; The equivalent magnesium solutions have not been studied. Although calcium "carbide" is used as a desulfuriz-ing reagent in steelmaking. and is possibly present as an acetylide-oxide phase in very basic electric arc practice slags, the acetylide ion appears to be substantially unstable in a silicate slag.* As a conse- *This instability arises from equilibria in the reaction: CaC2 + CO = (Ca0) + 3C where the low intrinsic solubility of CaC2 in silicate lattice, and the low activity of CaO in a silicate solution where CaO/Si02 < 1, combine to give a very small equilibrium concentration of CaC2 in solution in such silicate slags at temperatures in the region of I 500°c, even under carbon-saturated conditions. Under highly basic conditions, a liquid CaO-CaC2 phase may separate from the silicate system quence of this, the possibility that reactions involving CaC2 in silicate solutions are of importance to general steelmaking practice is remote. However, in operations involving a slag primarily based on a halide, or alkaline earth oxide, we must take into account the possibility that CaC2 will appear in quantities sufficient to significantly affect both the chemical and physical properties of the slag. The work outlined below presents a study of the CaF2-CaC2 system intended to provide sufficient data to allow an estimate of the importance of this system to electroslag remelting and welding practice. However, we should indicate at this point that there will be other processes, e.g., heat treatment, flux cleaning of castings, fused salt electrolysis, and so forth, where alkaline-earth halide fluxes are in contact with carbon, graphite, or carbides, and where halide-acetylide solutions must be taken into account. EXPERIMENTAL 1) Structural Studies. In view of the difficulty ex-perienced in handling CaC2 prepared from calcium turnings and propane gas at 700°C, it was decided to use solutions prepared directly in the equilibration apparatus, Fig. 1. The starting materials were: a) Ni-Ca-C alloy, prepared by adding calcium to liquid nickel held under calcium fluoride in an induction-heated graphite crucible; b) calcium fluoride, prepared by fusing calcium fluoride powder (British Drug House "EXTRA PURE") calcium fluoride in an induction-heated graphite crucible, in air, followed by electrolysis between graphite electrodes at 1 amp cm-2 density, for 10&apos; coulombs per g CaF2. This procedure decomposes the CaO produced by hydrolysis during the fusion step, replacing it by CaC2; Ca2+ + 2e-Ca*(l) Ca*(l) + 2C(gr)-(CaC2)caF2 O2- -2e-O*(g) O*(g) +C(gr)-CO(g) This results in a composition of between 2 and 5 wt pct CaC2 in CaF2. Fifty grams (in lumps) of this material were placed in a graphite crucible, together with Ni-Ca-C alloy (averaging 20 wt pct Ca), and the equilibration apparatus assembled. The alloy reacted with the crucible at high temperature to give CaC2, which dissolved in the calcium fluoride solution to give the desired composition. Cooling curves were plotted manually for these liquids, with rapid stirring and CaF2 seeding to minimize supercooling, and using a Pt/Pt 13 Rh thermocouple calibrated on the freezing points of nickel and copper. This gave a reproducibility of ±0.l°C. and an absolute accuracy of the thermocouple of ±l°C. An example curve is shown in Fig. 2, with the CaF2 end of the binary system in Fig. 3. The CaF2-CaC2 ingots were crushed, under dry nitrogen, and sampled for chemical analysis and X-ray examination. Analytical details are given in the Appendix. Powder diffraction data indicated that the only phases present in all samples examined were calcium fluoride and tetragonal (Types I and 111) calcium acetylide,4 with no evidence of solid solutions or compound formation. 2) Thermochemical Studies. The apparatus used to obtain activity data on CaC2 in these systems is shown in Fig. 4. It consists of an arrangement whereby the graphite crucible and its contents (CaF2-CaC2. Ni-Ca-C) can be rapidly cooled without exposure to air. Trial experiments to determine an equilibration time by ap-

Jan 1, 1969

By W. F. Rochow, W. C. Burke

Numerous designs of linings and accessories, including dams, lifters, and heat exchangers, contribute greatly to kiln efficiencies. Greater conductivity is achieved with basic brick than with fireclay and high-alumina refractories, depending largely upon the use of steel plates in radial joints between adjacent brick to increase heat transfer through the lining. Refractory lifters expose all portions of the load to radiant or convective heat and raise some portions to higher temperatures by cascading the load down through the path of the hot gases.

Jan 3, 1955

By J. P. Neumann, L. Raymond

At temperatures near 1000°C, only the (112) (111) slip systems are operatire in tungsten. Therefore, the substructure introduced into the billet upon rleforming a single crystal by rolling at 1000 "C can be controlled by proper selection 01. processing ral&apos;iubles. Using a reduction of 10 pct pel- pass, the (001)[110] and the (110)[001] crystals will deform by duplex slip rip to a 50 pet reduction in thickuess. These rolled single-crystal sheels are characlerized by anisotropic hardening, retention of ductility with warm working, lattice bending which is related to the conlacl (angle, and macroscopic dimensional changecs in the length bid not the width of the billet. When several slip systems become operative, a greater degree of work hardening is itztvoducetl into the crystal. This rolling- condition is characlerized by isotropic hardening, loss of ductilily with warm working, complex lattice distortions, and macro-scopic dimensional changes in both the length rind Width of the billel. IN tungsten, the {1 10}(111) slip systems are operative below room temperature,&apos; while above 700°C only the {112{ (111) slip systems are observed.2,3 In the transition region, i.e., room temperature. both systems appear. It is the purpose of this investigation to show that tungsten single crystals deformed by rolling at a temperature where only one slip system is operative generate dislocation substructure which depends on the crystal orientation. For a specific crystal orientation. the resulting dislocation substructure can be further influenced by modifying the rolling procedure. Crystals oriented for multiple slip display less substructural sensi- tivity to modifications in processing techniques than do single crystals oriented for duplex slip. Under simple slip modes of deformation, very little work hardening is introduced into a rolled single-crystal sheet. Mechanical properties such as room-temperature strength. ductility, and hardness are used to confirm the existence of the different work-hardened conditions generated within the crystal by modified warm-rolling techniques. EXPERIMENTAL PROCEDURE Material. Single-crystal billets of four different crystal orientations. grown by the Arc-Verneuil technique. were ground to a size of 0.25 by 0.375 by 3 in. In terms of their rolling plane and rolling direction, the billets had the following orientations: (1101 [001 ] (110) [110] (001) [110] (001) [100] The actual orientation of all crystals was within 5 deg of the ideal orientations. The typical impurity content of the crystals is given in Table I. Polishing and Etching. Polishing was done elec-trolytically in a 20 g per liter aqueous solution of NaOH at approximately 10 v. It was established by the Laue back-reflection X-ray technique that the surface damage due to grinding and cutting operations with a diamond wheel did not exceed 0.001 in. Therefore after each cutting or grinding operation at least 0.002 in. was removed electrolytically from the surface in order to eliminate surface effects. By lowering the voltage to 3 v, subgrain boundaries and individual dislocations are identified in agreement with Berlec 4 where the etch-pit traces on a cubic plane form a square. The etching time was about 5 sec at room temperature. Rolling. Rolling was carried out on a Loma 2-high mill (Model 600). The peripheral velocity of the 6-in.-diameter rolls was 500 in. per min, with the surface temperature of the rolls about 400° to 450° C The billets were heated before each pass for 30 min in argon to 1000 C. Oxidation of the crystals during rolling in air resulted in a thin layer of greenish-yellow WO 3 This oxide was removed after each pass by immersing the crystals for a few minutes in a boiling NaOH solution. Prior to the initial rolling pass, a surface layer of 0.001 in. was removed by polishing. The crystals were then annealed in vacuum (10-4 torr) at 2400 C for 30 min. All crystals were rolled in the same direction; i.e., the same end was always introduced into the rolls. The rolling program was conducted in

Jan 1, 1965

By Bain, Edgar C.

THE results are presented of an investigation to discover the fundamental atomic conditions existing in Corson&apos;s high-copper alloys hardenable by means of silicide solution and reprecipitation. The study attracted the writer because it offered a very convenient example of the general type of hardenable alloys exemplified by duralumin. Sykes&apos; iron-tungsten and iron-molybdenum alloys and the hardenable lead-antimony. SUMMARY OF RESULTS AND CONCLUSIONS In brief, the investigation shows that very perfect crystallinity exists in the solid solutions prepared at high temperature to contain as much dissolved silicide as possible. The lattice parameter of copper is altered very little by the amount of cobalt, nickel or chromium, and silicon dissolved. The hardening by drawing at a temperature to initiate precipitation of excess silicon and metal produces a remarkable change in the atomistics of the solid solution. The old perfection of crystallinity in the solid solution is destroyed and the new atomic spacings are of variable magnitude even in one grain, and a condition in a measure resembling that found in martensite is observed. Were no particles whatever precipitated by the drawing action, still ample causes for hardness would be in evidence in the solid solution alone. The lack of plane continuity in the crystal grains would oppose slip in a very effective manner. Complete annealing restores the crystalline perfection in large measure. In these alloys even the most sensitive methods failed to reveal the characteristic pattern of the silicide precipitated by the anneal, but this was largely to be expected as the amount is relatively small.

Jan 1, 1927

By R. C. McFarlane, T. D. Mueller, J. E. Walstrom

In evaluating uncertainty, experiments are usually performed repeatedly and then conclusions are drawn from the distribution of results. With the advent of high-speed electronic computers, it is possible to perform experiments using mathematical models constructed to simulate complex experiments or operations. Statistical methods are then applied to the results of the simulated experiments. This procedure forms the busis of this paper. Demonstrated is the need for properly accounting for uncertainty in petroleum engineering problems. How uncertainty affects solutions is evaluated in three example illustrations. The method used to evaluate uncertainty in petroleum engineering studies is the Monte Carlo simulation procedure.&apos;-" INTRODUCTION The solution to most technical problems may be derived from interrelationships among several quantities called variables or parameters. There may be only a few variables or several hundred. Interrelationships among parameters may be explicit or implicit, well established or only approximate. Some variables that fully or partially depend on the magnitude of others are called dependent variables. Input variables for most practical problems are not precisely known; there is usually an uncertainty in their value. The degree of uncertainty may vary from one variable to another. Variables that are known accurately are called determinates.&apos; For instance, the gravity of crude obtained from a particular pool may be known precisely, and therefore is a determinate. The degree of precision with which a quantity can be determined increases as data describing the pool are accumulated during the development of the field and the producing life of the pool. The uncertainty of a parameter may result from difficulty in directly and accurately measuring the quantity. This is particularly true of the physical reservoir parameters which, at best, can only be sampled at various points, and which are subject to errors caused by presence of the borehole and borehole fluid or by changes that occur during the transfer of rock and its fluids to laboratory temperature and pressure conditions. Uncertainty may also result in attempting to predict future parameter values. This type of uncertainty is particularly evident in investment analyses involving future costs, prices, sales volumes and product demand. Uncertainty in the solution to investment problems is often called risk, and its study is called risk analysis.&apos; Uncertainty also enters into biological and sociological analyses in which indeterminate factors are often important due to limited control of the experimental material. It is customary, in evaluating uncertainty, to perform repeated experiments and to draw conclusions from the distribution of the results of these experiments. With the advent of the high-speed electronic computer, it is possible to construct mathematical models which simulate complex experiments or operations and to perform the experiments repeatedly, utilizing the models. Statistical methods are then applied to the results of the simulated experiments This method forms the basis of the investigation reported here. PROBABILITY DISTRIBUTIONS FOR VARIABLES The uncertainty in the value of a variable may be indicated by a probabilistic description accomplished by expressing the quantity by a probability distribution. Many recognized probability distributions can be used to describe physical quantities. Recent studies used various types of distributions to describe core analysis data.&apos;,&apos; However, for the examples in this paper, the uniform and triangular distributions are believed to reasonably approximate the data used (Fig. 1). The uniform distribution confines the variable between an upper and a lower limit. The variable may lie anywhere between the two limits. This distribution is used when no one range of values for a variable is more probable than any other, but information or intuitive reasoning indicates the variable will lie somewhere between the chosen limits. The triangular distribution is used for a variable when more data are available to indicate a central tendency of distribution. This allows postulating a "most likely" value to the distribution and upper and lower limits. In this case, as for the uniform distribution, the variable is not expected to assume a value less than the lower limit or greater than the upper limit. However, with improved quality of data it can be postulated that the variable will tend to assume a value close to the most likely value, and that there will be a decreasing probability for values away from the most likely value. The area under either of these probability distributions is equal to unity since it is assumed that there is a 100 percent probability that the variable will lie somewhere under the curve. An ordinate erected at any particular value of the variable divides the area under the curve into two parts: the area to the left of the ordinate represents the probability that the value of the variable will be equal to or less than the value of the variable at the position of the ordinate, and vice versa. The probability is zero that the variable will have any specific deterministic value. If two ordinates are drawn for any two values of the variable, the probability that the variables will have a value lying between these ordinates is equal to the area under the curve lying between the ordinates.

By F. L. Grammer

In these day, when anthracite is less extensively used as a blastifurnace fuel than it was a generation ago, and managers endeavor to maintain regular and known ore-mixtures, the " freezing " of tuyeres, cinder-notch or iron-notch is infrequeut; and, consequently, the oil-burner or " kerosene blowpipe "* is seldom employed; and furnace-foremen have, to a considerable degree, forgotten their former cunning and persistency in the use of the drill and sledge. Still, in starting new or abandoned plants with untrained labor, and in running some of our large 100-ft. furnaces, slips, resulting in very cold furnaces, may occur, even under experienced managers. During my superintendence of the Cleveland, O., blast-furnaces, such a misfortune, owing to a dearth of trustworthy foremen, was experienced; and our electrician, Mr. Thomas Martin, proposed to open the tuyeres and cinder-notch by means of the heat of the electric arc. We have heard that the surface-cracks or marks developed in rolling heavy plates have been closed by electric welding, as by a soldering-iron, and also that an electric burner has been employed at some German blast-furnaces; but the experiment was quite novel to us; and I think it constituted one of the first, if not the very first, successful application of this device, for the purpose named, in the United States. †

Jan 1, 1902

By John C. Cosgrove

IT was just five minutes past midnight, on Wednesday, Jan. 5, 1938, that Mrs. Cosgrove and I sailed from New York City. Our trip was to completely circle the globe, to cover over 40,000 miles and stop at thirty ports-from New York to Trinidad, to South America, via South Africa to the Orient, to India, to the Malay States, to Indo-China, the Philippines, Australia, New Zealand, Fiji, and across the Pacific home via Honolulu. It is not my intention to make this a complete, technical study of coal or coal mining in the various countries that .we visited but more to outline the general in- formation that the mining engineer and coal operator would absorb in his travels. Coal is the universal fuel and is in use wherever there is commerce and industry. Even on our ship, which, like practically all ocean liners was an oil-burner, a considerable quantity of coal was used for cooking.

Jan 1, 1939

By H. J. Ramey

Conventional calculation of total system isothermal compressibility for a system containing a free gas phase involves, among other things, evaluation of the change of oil and gas formation volume factors and the gas in solution with pressure. Preferably, this information should be obtained from laboratory measurements made with particular oils and gases. Often, experimental measurements are not available. In this case, it is necessary to obtain pressure-volume-temperature relationships from general correlations such as those of Standing&apos; for California oils. In order to speed estimates of compressibility, generalized plots have been prepared of the change of both oil formation volume factors and gas in solution, with pressure from Standing&apos;s correlations. A generalized plot for estimating the change in the two-phase (oil and gas) formation volume factor with pressure is also presented. Usually, the effect of gas dissolved in reservoir water upon the total system compressibility is neglected for gas saturated systems, due to the low solubility of gas in water. Results of this study indicate that the increase in total system compressibility caused by solution of gas in water is often as large as the compressibility of wafer, and can be magnitudes larger for low pressure systems. Generalized results for estimating the change of gas in solution in water with pressure are presented in tabular and graphical form. INTRODUCTION During the past decade, pressure build-up and drawdown techniques have gained an important place in reservoir engineering. Build-up and drawdown analyses are only two special applications of the broad field of transient fluid-flow theory. All solutions of transient fluid-flow problems contain a parameter called the total system isothermal compressibility. This property of fluids and porous rock is a measure of the change in volume of the fluid content of porous rock with a change in pressure, and it may vary considerably with pressure. Evaluation of total system isothermal compressibility is not difficult, but it is tedious and time-consuming. Often compressibilities are estimated roughly, or transient flow methods are neglected completely. The benefits of using accurate system compressibility in properly-executed build-up or drawdown analyses are: 1. Better planning of pressure build-ups may be achieved to avoid unnecessary loss of revenue due to excessively long shut-in periods, or to shut-in periods too short to yield useable data. 2. Better and more reliable estimates of static formation pressures for reserves estimates and rate performance estimates. 3. Reliable information for evaluation of well completion effectiveness, and planning and interpretation of well stimulation efforts. The purpose of this paper is to clarify the nature of the total system isothermal compressibility, and to present useful methods for estimation of compressibility, particularly for systems containing a gas phase. DEVELOPMENT Numerous publications have presented solutions to transient single-phase flow of slightly compressible fluids, stressing pressure build-up applications. In transient flow, a compressibility* term arises to permit volume content of fluids in porous rock to change as pressure changes. The basic nature of the compressibility term is usually taken for granted. Problems arise in practical applications of transient fluid theory because most published works consider only one flowing fluid—in an ideal porous system containing only one fluid. In 1956, Perrine2 presented an intuitive extension of single-phase flow pressure build-up methods to multiphase flow conditions. Later, Martin- established conditions under which Perrine&apos;s multiphase build-up method had a theoretical foundation. Perrine has shown that improper use of single-phase build-up analysis in certain multiphase flow situations can lead to gross errors in estimated static formation pressure, permeability and well condition. It is likely that, much pressure build-up data for oil wells should be analyzed on the basis of multiphase flow. For both single-phase and multiphase build-up analysis, the isothermal compressibility term in dimensionless time groups often should be interpreted as the total system compressibility. All real reservoirs contain one or more compressible fluid phases. In addition, rock compressibility can contribute in an important way to the total system compressibility. The proper total system compressibility expression may contain terms for compressibility of oil, gas, water, reservoir rock and terms for the change of solubility of gas in liquid phases.

Jan 1, 1965

By John Rear Admiral Edwards

Introductory.-There are many interesting and important events connected with the petroleum problem. The remarkable men who conceived the thought of transporting petroleum by pipe line, conserving the by-products of the commodity, and conducting extended investigation and research whereby the flash point of the oil was raised, its cost reduced and its Supply assured, are deserving of the gratitude of this nation. It was primarily the success attained by Captain Lucas, after his comprehensive search for oil in Texas and Louisiana, that was the impelling cause. which &apos;prompted the Navy Department to conduct the extensive series of liquid fuel-oil tests that were made from 1901 to 1903. The sensational discovery of oil at Spindle Top made a deep impression upon Rear Admiral George W. Melville, then Engineer-in-Chief of the Navy, and the discovery of the vast oil field in Texas convinced him that, within a generation, if not within a decade, crude petroleum was going to play a very important part in warfare, and that the commodity might possibly develop into a necessary munition of war. The United States&apos; Commanding Position as a Petroleum Producer.¬ In the study of the various problems relating to the world&apos;s production of crude petroleum, the position of the United States is one of commanding importance, whether viewed from the industrial or the military aspect. The present yield of this country is practically double that of the rest of the world, and, in view of the productive and prospective fields possessed by various countries, together with the comprehensive and exhaustive search that has been made throughout the world for petroleum, it is extremely probable that this lead will be maintained for the next decade. As regards the character of the crude-oil yield of different countries, America possesses the greater part of the supply that contains a paraffine base, and therefore a considerable portion at least of the American product produces the best illuminant. Of all the crude-oil distillates, kerosene is in many respects the most important, and the Appalachian product for this purpose is favored, particularly in the Far East, above that of any other petroleum yield of the world.

Jan 9, 1914

By P. Shahinian, M. R. Achter

In a comparison of the creep -rupture properties of nickel in air arid in vacuum there is a reversal in relative strengths with variations in stress. At low stresses the properties are better in air while at high stresses they are better in vacuum. In the early stages of creep in a high stress test the specimen in air nzay have the lower creep rate but the one in vacuum is creeping at a lower rate in the later stages. A mechanism, involving two competing processes in terms of oxidation strengthening and weakening by surface-energy reduction, is proposed to explain these reversals. It had generally been assumed that, relative to their properties in air, the high-temperature strengths of metals would be increased in an inert atmosphere as a result of the elimination of the deteriorating effects of oxidation. However, several recent investigations have shown that the creep strength may be greater in air than in nonoxidizing gases. Pickus and Parker1 found that the creep rate of nickel was lower in air than in hydrogen or nitrogen. Internal oxidation was mentioned by Shepard and Schalliol as a possible cause for the longer creep life of Hastelloy C in air than in vacuum or helium. Sweetland and Parker, who observed lower creep rates for aluminum and copper in air than in helium, discuss the possible applicability of the dislocation-barrier mechanism to explain their results. Surface oxide layers may interfere with the escape of dislocations through the surface or with their generation there. In addition to showing the strengthening in air of low-alloy and stainless steel, and nickel and cobalt-base alloys, shahinian4 presented notch-effect data which indicate the role of stress concentrations; alloys of relatively low ductility were more sensitive to atmosphere strengthening when notched specimens were used. Although Bleakney&apos;s copper wires had a lower reduction of area in air than in vacuum, it is difficult to interpret his results in terms of strength changes since the stresses employed were not measured. In contrast to these data showing the strengthening in air, a number of investigations, most at relatively low temperatures, have demonstrated that the environment may cause a decrease in strength. These results are generally explained in terms of the effect of environment on surface energy. In a review of the subject, Benedicks and Harden use the concept of atomic bonding to explain how the adsorption of impurities would decrease the energy of a clean surface. A decrease in surface energy would facilitate the propagation of cracks or extension of the surface. Use of this mechanism is made by sato7 to explain the weakening of steel specimens bent in various liquids, by Potek and Shcheglakovs for the reduction of fracture strength of steel in molten metal, and by Benedicks and Harden for the reduction of strength of a variety of materials in a number of liquids. A similar explanation might be used for the results of Forestier and Clauss. The fracture stress of fine wires pulled in a variety of gases, including air, is lower than in vacuum. They attributed their results to the "tendency" for the gases to condense on the metal surface. That the strength of metals is affected by the type of gas in which the test is conducted has been demonstrated convincingly; the mechanism of the effect, however, is still uncertain. This investigation represents one in a series to explore the influence of variations in alloy composition and test conditions on the atmosphere effect in the expectation that the results would afford an insight into the processes taking place. To determine the effect of specimen composition, the present investigation was conducted

Jan 1, 1960

(Under this heading will be published notes sent to the Secretary of the Institute by members or other persons. ) A member, technically educated, with 20 years&apos; practical experience as engineer, assistant superintendent, superintendent, and manager of large mines and mills on construction and operation, also experience in mine examination, is open to engagement. Metallurgist of 18 years&apos; experience in Mexico with large plants is open to engagement. Last position, superintendent of copper smelting works. Best line, copper and lead smelting, but also experienced in mine valuation and ore-treatment investigation work. Speaks Spanish. A member of the Institute and graduate mining engineer with 10 years&apos; experience in the Lake Superior copper district, also practical experience, desires position as superintendent or manager. Member, graduate mining engineer, experienced in mine and mill work, geology and field work, one year in the hydrometallurgy of copper, is open for engagement Aug. 15. A member, at present in the Southwest., desires a position as assistant superintendent or assistant manager with a mining company operating in Washington or Alaska. Experienced assayer and engineer. A member, technical graduate, with nine years&apos; mining experience as assayer, engineer, foreman, manager&apos;s assistant, and superintendent of large development and operating mining companies in the United States and Mexico, is open for engagement. A member, technical graduate, 33 years of age, 11 years&apos; experience as chemist, metallurgist and superintendent of lixiviation plant and in charge of construction of cyanide mill, desires position as assistant superintendent or superintendent of mining or milling company in United States or Canada. Young man, technical graduate, two and a half years&apos; experience in chemical laboratory, desires position as chemist.

Jan 9, 1913

By Howard A. Meyerhoff

In western Argentina, in the Province of Mendoza and the Territory of Neuquen, there is a series of solid bitumen deposits which are claimed to be the most extensive in the world. In a linear belt 500 km (311 miles) long, roughly paralleling the axis of the Andes but occupying a variety of positions with respect to the orogenic structures, more than 100 outcrops have been reported. Approximately 70 of these have been prospected, and some mining has been planned or attempted for about half this number. Limited tonnage, high sulphur content, inaccessibility, labor shortages, and disastrous fires have taken a heavy toll among these operations, and in 1947, only 4 deposits were being actively mined, but 8 more were being explored and developed with a view to placing them in production. Inasmuch as these deposits are currently yielding a substantial fraction of Argentina&apos;s limited domestic supply of solid fuels, a brief account of the deposits and of the small industry based upon them will provide a commentary on Argentina&apos;s fuel problem. Character of Solid Bitumens The solid bitumens of Mendoza and Neuquen are petroleum derivatives, as is indicated by the following ultimate analysis : Constituents Per Cent Hydrogen.................... 6.8 Carbon...................... 82.4 Nitrogen..................... 1.6 Oxygen...................... 2.7 Sulphur...................... 2.2 Ash.......................... 4.3 100. 0 In physical appearance they bear a close resemblance to coal and are commonly called carbon. Their specific gravity has an extreme range of 1.10 to 1.777 in 36 samples weighed, but the average is between 1.14 and 1.24. The material is black, lustrous to dull, with blocky to sub-con-choidal fracture. Though brittle, the purest material is softer than anthracite and exhibits slightly more cohesion. This bituminous material is generally known as asfaltita or asphaltite, but definitive chemical studies indicate that the term asphaltite or grahamite can be applied correctly only to the exceptionally pure material of the Auca Mahuida district in Neuquen. Some other name should be used for the chemically variable bitumens found in all other districts, and the designation "asphaltitic pyrobitumen" has been proposed by Carlos A. S. Piscione.1 At the present time these bitumens are finding favor as solid fuel and as a gas-producing medium. They yield heat values of 8650 to 9750 cal,2 or 14,500 to 16,750 Btu per pound, and in consequence of their excellent heating qualities and the scarcity of imported coal, they are marketed as far away as Buenos Aires at a price of go to 95 pesos, or approximately $22 to 23, per metric ton. In burning, the material swells and decomposes into solid, fluid, and gaseous fractions which burn violently though nonexplosively. Its combustibility has been responsible for disasters and virtually complete destruction at Mina La Es-peranza and Mina Santa Marta, and for minor mishaps elsewhere, as at Mina Escondida in August 1947.

Jan 1, 1949

By P. H. Lindon, J. C. Billington

Fe-O melts containing 0.045 pct 0 were deoxidized with Mn-Si-A1 alloys. Product compositions were reluted to the melt and alloy compositions and were found to be most sensitive to the aluminum content of the alloy. Low residual oxygen contents could be obtained when aluminum oxide was present in the Products because of the reduction of silica and manganese oxide activities. Flotation of the Products from a quiescent melt was followed both by analysis of the oxygen content and metallographic measurement of inclusion concentration. MnO-SiO2-A12O3 products were found to float most rapidly when their composition was such that their viscosity may be expected to be low. Changes in the particle size distribution indicates that particle coalescence occurred and differences in the degree of coalescence are thought to be responsible for the different flotation rates observed between products 0f differing composition. Measured flotation rates were slower than those Predicted from a model based on Stoke&apos;s Law, although alumina flotation might be reasonably accounted for by this model. Interfacial effects between oxide particles and the melt are believed to be responsible for the discrepancy. It has been recognized that deoxidation products constitute a large proportion of the nonmetallic inclusions present in killed steel. The amount of oxide inclusions which originate as deoxidation products depends largely upon three factors. These may be summarized, according to P16ckinger1 as: 1) Amount of primary products remaining in the steel prior to cooling. 2) Residual dissolved oxygen content of the steel after deoxidation. 3) Amount of secondary products, formed during cooling and solidification, which remain entrapped in the solid steel. In a well-deoxidized steel containing residual aluminum and/or silicon, the equilibrium dissolved oxygen content is usually very low and so the maximum amount of oxide which may be produced as secondary deoxidation products is small in comparison with the amount of primary products. It may be seen, therefore, that the amount of indigenous nonmetallic inclusions may be minimized if a low dissolved oxygen content is achieved by deoxidation and if the primary deoxidation products are efficiently removed. Oxides which originate by reaction of the metal stream with the atmosphere during teeming are not considered in the present study. It is known that two or more deoxidizers may result in a lower equilibrium oxygen content when used in conjunction with one another than when any of the individual deoxidizers are used alone. Equilibrium studies by Hilty and crafts2 and by Bell3 have shown that manganese increases the effectiveness of silicon as a deoxidizer, and Walsh and Ramachandran4 relate this to a reduction in the activity of silica in the products as the manganese :silicon ratio in the steel increases. It was also shown by Herty&apos;s work on deoxidation of steel by silico manganese alloys,5 that there existed an optimum ratio of manganese to silicon which gave a minimum inclusion content. This ratio was in the range 4:l to 7:l and the (FeO-MnO-SiO2) products formed by such deoxidation practice were found to lie in a composition range having very low liquidus temperatures (1170 to 1250°C approx). The optimum manganese:silicon ratio was then explained by postulating that these fluid products were able to coalesce and that the larger particles formed floated out of the steel very quickly as predicted by Stoke&apos;s Law. The present work examines the effectiveness of various Mn-Si-A1 alloys as deoxidizers and their effects on the composition and removal of primary deoxidation products from a quiescent melt. EXPERIMENTAL TECHNIQUE Approximately 250 g of prepared Fe-O alloy, containing 0.045 to 0.055 pct O, were melted in an alumina crucible and deoxidized at 1550°C by plunging a thin steel cartridge containing the deoxidizer below the melt surface. A high frequency induction furnace supplying current at 8.5 kHz was used to heat a graphite susceptor, the interior of which had been machined to give a wall thickness of 0.85 in. to form a receptacle for the alumina crucible. The iron melt was essentially quiescent as the induced current was concentrated at the external surface of the graphite susceptor by the skin effect. A nonoxidizing atmosphere was maintained over the melt by passing a continuous stream of argon through the lid of the susceptor. The melt temperature was measured before deoxidation, and again at the end of an experiment by means

Jan 1, 1970

F. G. CLAPP, New York, N. Y. (written discussion *).-Whatever processes of appraisal have been found most correct and feasible in one field or group of fields will generally prove most adaptable in others. So far as the California fields are concerned, Mr. Requa&apos;s paper appears to outline the most up-to-date processes of appraisal. It remains, then, to discuss and adapt these and to make such revisions in methods and processes of calculation as will give us results elsewhere. The trouble about most attempts to place a value on oil lands, whether in this country or elsewhere, has been that many of the so-called "experts" called upon to express an opinion either have not possessed the requisite engineering and geological knowledge to make an accurate appraisal of the lands, or that they were not furnished with sufficient information for the purpose in hand. The Independent. 011. Producers&apos; Agency of California, for whom Mr. Requa&apos;s original report was prepared, had many advantages in this respect not generally available to engineers making reports, as all existing information seems to have been at the experts&apos; disposal within the limits of a large number of properties, practically commensurate with the extent of the fields in question. Hence the report could be and was more accurate than any similar report for a single company is likely to be in other fields. Very few companies are so exempt from competition that all the data on neighboring leases of other companies will be freely turned over to them. In many companies, certain available data are concealed from the engineer who makes the reports, particularly if the properties are supposed to be worth less than their apparent value. In the case of other companies, having the best of intentions, the data are insufficient to help the engineer greatly in his appraisal, simply because the oil business has been so, unsystematic in most fields that only the largest and wisest companies have kept accurate figures regarding runs and gravity of oil from individual wells and from different depths. In many wells, which ran wild for clays or weeks in the older fields, there was a waste which is not recordable with exactness. These and many other difficulties confront even the most experienced expert in actual practice outside of the California fields. We may justly say, therefore, that an engineer in other fields of the United States and in the European, South American and Asiatic fields, must not only begin where the Independent Oil Producers&apos; Agency

Jan 4, 1918

By William F. List, Marvin A. Schuster

Monolithic electrooptical mosaics of 2500 photo-transistor elements with internal row and surface column interconnections have been fabricated by epitaxial-planar diffsion techniques. Unique access to any elemed of the mosaic is provided through one of the fifty X and one of the fifty Y external leads. The sensor mosaic can be used for imaging applications and has a 1:1 aspect ratio, a resolution of 100 lines per in., a dynamic range in excess of lo3, a sensitivity of 0.5 per pw, element response within a 2:l range over 75 pct of the mosaic, and a minimum detectable signal of the order of 10-&apos; w. Design considerations which ilnpose particclar fabrication yequirements are disctussed along with some of the problems peculiar to the epitaxial and planar-dijfision techniqes by which this device is fabricated. The solid-state silicon monolith has an imaging area of 0.5 by 0.5 in. and an element center -to- center spacing of 0.010 in. J monolithic solid-state electrooptical device has been developed as the photon-sensing mosaic for use in an image-converter system.&apos; This system is the solid-state equivalent of the vidicon and can image radiation in the visible and near-infrared regions of the spectrum. The electrooptical image converter has the desirable size, weight, reliability, and low-power characteristics inherent in solid-state devices. It is read out by direct-wire means rather than by beam-scan techniques. The packaged unit is shown in Fig. 1. A selection of material for the sensor was based on considerations of both reliable fabrication techniques and material spectral response. Silicon was selected both for its response from the lower end of :he visible to the long-wavelength cut-off above 11,000A and for its well-developed epitaxial planar-diffused technology. The electrical image is composed of M x N discrete information bits with each bit emanating from one of the individual phototransistor sensors. The interconnected mosaic concept was introduced to provide a structure which is both manageable in its number of leads and compatible with conventional viewing systems which accept XY data. Interconnections along the Y direction are provided by internally diffused strips, while interconnections along the X direction are formed by vacuum-deposited metal surface bars. Unique access to any individual element of the M x N mosaic is available through one of the M and one of the N external leads. PHOTOTRANSISTOR DESIGN A phototransistor structure2 was selected for the discrete photon detectors of which the mosaic is com- posed. Basically, the mode of phototransistor operation is such that incident quanta are absorbed in the base area of the element where they generate electron-hole pairs. If the electrons are liberated within a diffusion length of the depletion region around the collector junction, they will diffuse to this depletion region and be swept across the junction where they account for a small component of the photocurrent. Similarly, the holes which are created within a diffusion length of the emitter junction will diffuse to this region where they forward bias the emitter and so induce injection of minority carriers into the base. This accounts for the substantial transistor photocurrent. This mechanism of operation implies several design and fabrication goals for the individual sensor elements: high electrooptical conversion efficiency, sufficient carrier lifetime in the base regions, and a maximum volume in which photons can be absorbed within a diffusion length from the depletion layer about the junction. Moderately high transistor gain is desirable to permit readout at low light levels; however, very high gain has a deleterious effect on mosaic dynamic range. The mosaic must also be characterized by good uniformity of element response as well as by good isolation between elements. The above set of conditions imply that junction depths must be optimized with respect to photon ab-

Jan 1, 1967

By A. B. Bowman

The 1963 Jackling Award lecturer describes the founding of Banner Mining Co. and its trials and tribulations before becoming an established firm. Such aspects as geological description of Banner mining areas, history of exploration and production, areas of present interest to the company and research work conducted by the company are included. Several years ago a wealthy Chinese business friend of mine purchased an interest in a proposed oil well to be drilled a great distance from his home. A few months later it came in as a producer and proved to be a huge success and materially added to his resources. I asked him why a man of his wealth should be so lucky in a venture outside his sphere of knowledge when most people of modest means never seemed to get ahead. His answer was, "Fat Hoy takes a chance." Even though this was his answer, I knew from my association with him that there were other tempering considerations which Mr. Hoy applied before making up his mind to enter any transaction. First, he was a cautious individual. He was also a great believer in details and insisted on knowing everything possible about a situation, and finally, he was what we call a very solid individual with good basic instincts and judgment. This philosophy of Mr. Hoy may be applied to most any business but especially to those engaged in a search for natural resources such as mining where great risks are involved. This article concerns events in the history and growth of Banner Mining Co., with which I have been associated for 27 years in capacities from mine surveyor to vice president. Mr. Hoy&apos;s philosophy has played a significant role in the exploration projects of this company over the years, but what is more important, the officers, directors, and controlling interests in Banner have been aggressive in their search for ore reserves. THE BIRTH OF BANNER Banner Mining Company was incorporated in September 1935 by a group of Oklahoma and Texas oil men for the purpose of exploring and developing the Bonney-Manilla mines at Lordsburg, N.M. These properties had a history of intermittent production since the first ore discoveries as far back as 1870. Most of the production from the district has come from four mines, namely, the Eighty-Five, the Atwood, the Bonney-Manilla, and the Misers Chest. The last two are now owned by Banner Mining. The Eighty-Five mine operated between 1885 and 1931, and production totalled 1,494,287 tons averaging 0.11 oz of gold per ton, 1.23 oz of silver per ton, and 2.80% copper. The vein extended for a distance of about 3000 ft northeast and was mined to a depth of 1650 ft. The Atwood mine, adjoining the Eighty-Five mine, to date has been of lesser importance as a producer, but it has been operating for several years producing high silica flux ores for a smelter. Production totalled 352,828 tons up to January 1, 1962 From the Bonney-Manilla and Misers Chest mines, owned by Banner, production through 1961 totalled 2,006,343 tons with an average grade as mined of 0.0192 oz of gold per ton, 0.760 oz of silver per ton and 2.63% copper. Banner built a 150-tpd flotation mill in 1936 after almost a year of development on the 600 level of the Bonney mine. After less than one year&apos;s operation, it became apparent that the 150-tpd rate was not sufficient to make a reasonable profit due to the marginal grade ores. The low tenor of the ore, mainly chalco-pyrite in a highly siliceous gangue, made mandatory the close control of costs in order to make ends meet. A 300-tpd unit was added to the mill in 1937, and it is still the operating unit today. The clean sulfides presented no problems in milling. A metallurgist doing research on it at the time stated that the copper minerals seemed to have a built-in desire to float. Mill recovery of copper throughout the 27 years of operation has averaged 96.23%. A PERIOD OF FORCED GROWTH World War II brought many hardships to Banner. Labor and supply shortages caused drastic curtailment in development work. Rapidly rising costs far outdistanced any relief from pegged prices which we received from Government agencies. Finally, a branch of the Government asked us to stop all devel-

Jan 1, 1963

By F. M. Lewis, J. F. Meyers

In the mining and handling of sulphide ores, some degree of oxidation takes place on the sulphide surfaces, which are exposed to the atmosphere. It is, moreover, well known that the oxidation compounds formed are a factor when such ores are subsequently treated by flotation. Modern operating technique and reagents are capable of contending with this condition to a major degree, provided that the proportions of the reagents used are varied correctly. This is particularly true at the Tennessee Copper Co., where the ore treated contains pyrrhotite in addition to other sulphides. A number of soluble salts, some of which are unstable, can be formed during the oxidation of the sulphide ores. Those unstable salts, whose oxygen requirements are unsatisfied, are constantly changing to more stable forms because oxygen reacts with them during the crushing, grinding and other operations of ore preparation. We add no chemicals of any kid to the ore pulp in its preparation for flotation feed. Consequently the only compounds that are present in the flotation feed are those produced by the natural oxidation of the ore in the presence of air and water. The Tennessee Copper Co. ore is composed of from 60 to 70 per cent sulphides and from 40 to 30 per cent non-sulphide material. It is not the purpose of this paper to discuss the nature of these various oxygen-sulphur compounds nor their effect on flotation, but to describe a method for correcting the effect. Suffice it to say that we have found that the reducing sulphur and oxygen salts have a depressing action on our bulk flotation process.&apos; From long experience we find that the best means of correcting for this variation in our work is to increase or decrease the quantity of xanthate, the promoting agent, as the quantity of the reducing salts increases or decreases. It was, therefore, very desirable to provide the operators with some quick and

Jan 1, 1947

By F. M. Lewis, J. F. Meyers

In the mining and handling of sulphide ores, some degree of oxidation takes place on the sulphide surfaces, which are exposed to the atmosphere. It is, moreover, well known that the oxidation compounds formed are a factor when such ores are subsequently treated by flotation. Modern operating technique and reagents are capable of contending with this condition to a major degree, provided that the proportions of the reagents used are varied correctly. This is particularly true at the Tennessee Copper Co., where the ore treated contains pyrrhotite in addition to other sulphides. A number of soluble salts, some of which are unstable, can be formed during the oxidation of the sulphide ores. Those unstable salts, whose oxygen requirements are unsatisfied, are constantly changing to more stable forms because oxygen reacts with them during the crushing, grinding and other operations of ore preparation. We add no chemicals of any kid to the ore pulp in its preparation for flotation feed. Consequently the only compounds that are present in the flotation feed are those produced by the natural oxidation of the ore in the presence of air and water. The Tennessee Copper Co. ore is composed of from 60 to 70 per cent sulphides and from 40 to 30 per cent non-sulphide material. It is not the purpose of this paper to discuss the nature of these various oxygen-sulphur compounds nor their effect on flotation, but to describe a method for correcting the effect. Suffice it to say that we have found that the reducing sulphur and oxygen salts have a depressing action on our bulk flotation process.&apos; From long experience we find that the best means of correcting for this variation in our work is to increase or decrease the quantity of xanthate, the promoting agent, as the quantity of the reducing salts increases or decreases. It was, therefore, very desirable to provide the operators with some quick and

Jan 1, 1947

By Carl E. Swartz

Although a number of articles appeared during the war advocating the use of cadmium in lead-tin solders, very little information of value can be found in the literature regarding the properties of solders containing cadmium. In most of the published articles the cadmium seems to have been considered merely as a partial substitute for tin in a tin-lead alloy rather than as an essential constituent of a ternary alloy. The primary object of the substitution of cadmium for tin was to lessen the amount of tin required, at a time when the latter was scarce and high-priced, and thus to produce a cheaper solder. While this object was accomplished, the new properties resulting from a change from a binary lead-tin alloy to a ternary lead-tin-cadmium alloy were not given proper consideration in many cases. For the past few years, the American Smelting & Refining Co. has been marketing a very considerable amount of cadmium in the form of lead-tin-cadmium alloys for use as solders for certain special purposes, and the successful use of these solders suggested that if more extensive knowledge were available concerning the properties of lead-tin-cadmium alloys of various compositions their field of usefulness might be materially extended. The investigation described in the present paper was undertaken to obtain this information and, by means of tests under conditions approaching those of practical use, to determine the suitability of cadmium solders for various purposes. Characteristics and Requirements of Solders in General General Physical Properties.—When cast into bars, solder should present a smooth and bright appearance free from oxide inclusions and bubbles. Ductility should be as great as possible without sacrificing tensile strength, and vice versa. Hardness and specific gravity are not of any great importance. Melting Characteristics.—The melting or solidification range is important. This statement applies both to the extent of the range and to the actual temperature at which complete solidification occurs. A rather narrow solidification range is desirable in soft solders in order that solidification may take place quickly. The solder should have high fluidity at temperatures only slightly above its melting range. For a

By W. G. Sinclair

The wartime momentum of exploration continued throughout the year 1945 despite the end of hostilities in mid-August. The table below illustrates drilling activity in the various categories: Completed wells. . . . . . . . . . . . . . . . . . . . . . . . 401 Wildcats.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104 Wildcat discoveries, oil.. . . . . . . . . . . . . . . . . . . 2 Wildcat discoveries, gas-condensate.. . . . . . . 4 Development wells.. . . . . . . . . . . . . . . . . . . . . .297

Jan 1, 1946