Search Documents

By AIME AIME

T HE Mid-Continent Section of the Petroleum Division met on Mar. 11 in the engineer's room of the Tulsa Building, Tulsa, Okla., for the purpose of reviewing the papers presented at the annual meeting in New York. L. G. E. Pignell, chairman and delegate to New York for the Mid-Continent Section, read a brief report giving the outstanding features of the various papers that were presented. He expressed regret that more members of the Division could not be present in New York to hear the interesting papers and discussions. It was his opinion that the various remedies presented for overproduction seemed rather theoretical and impractical and he recommended that the engineers come to the aid of some of the economists in giving more practical consideration to the overproduction problem.

Jan 1, 1929

By O. J. C. Runnalls, L. M. Pidgeon

J. M. Blocher, Jr. and I. E. Campbell (Battelle Memorial Institute, Columbus, Ohio)—Since the de Boer-Van Arkel process for making titanium metal involves a number of steps in a fairly compact unit, it is difficult to determine simply which of the steps is rate controlling. In any statement as to which step constitutes the rate-controlling process, qualifications appear to be in order. It is possible to design a reaction bulb in which any one of a number of steps is made to be controlling. I—With the filament removed some distance from the crude, as in the case of the authors' experiments, the interdiffusion of iodine and iodide may be controlling. 2—If, as is usually done, the crude metal is placed in a perforated cylindrical basket, or as a briquetted mass, in close proximity to the filament, the rate of deposition is increased (we obtained rates of deposition 5 to 10 times those cited in the authors' paper), and another rate-limiting factor, such as the reactivity of the crude, may take over. In this regard, we have noticed radically different rates of deposition with different crudes, and with crudes in various stages of exhaustion. 3—With a very reactive crude metal and with optimum practical geometry, still another process may be controlling. It is felt that this is a diffusion process in the immediate vicinity of the filament involving the fundamentally adverse situation of a net flow of particles away from the filament. The separate experiments on the reactivity of iodine with titanium are interesting but somewhat inconclusive. Data is still needed on the partial pressure of iodine in an operating decomposition bulb. A knowledge of the gradient of iodine partial pressure from the crude to the filament would be particularly enlightening. Optical absorption may be a useful technique here. Accurate measurements of the total pressure within a decomposition bulb under various conditions would be quite revealing. Preliminary measurements have been made at Battelle in following this line of attack. It is interesting to note that the authors' data on the temperature dependence of deposition rate indicate that the overall rate is not controlled by the kinetics of the decomposition reaction at the filament: TiI1 ? Ti + 4I Any reasonable estimate of the activation energy of this reaction would, if its kinetics were controlling, dictate a much greater temperature dependence than is observed here. The authors apparently attribute the drop in deposition rate (eventually to zero) with increased TiI4 pressure solely to a decrease in diffusion rate. However, there is an equilibrium factor involved here that must not be overlooked. As the partial pressure of TiI4 is increased, a point is reached where, due to the competing reaction of the tetraiodide with titanium to form lower iodides, the equilibrium partial pressure of titanium is reduced to the point that it equals the vapor pressure of titanium at the filament temperature and the deposition rate falls to zero. This effect would

Jan 1, 1953

By AIME

ENGINEERS have long pondered the answer to the question of "How am I doing?" and in large measure the answer from the economics angle is provided by the 1946 survey of the engineering profession now being published by the Engineers Joint Council as an eighty-page bulletin entitled "The Engineering Profession in Transition." The survey, based upon a completely precoded mail questionnaire, aimed at three major objectives: (1) to determine the general impact of World War II upon the profession in the period 1939 through 1946; (2) to obtain re- R liable data from which valid findings could be derived to predict how active the profession would be after 1946; and (3) to determine if the war's upheaval had changed materially the pattern of professional activities, education, background, and earnings from those which existed prior to 1939. Abundant data on the economic status of the engineer based upon years of experience in his particular field, the specific branch of the industry in which he served, and his educational background are presented. Relationships between years of experience

Jan 1, 1947

By Stanley J. LeFond, Neal Davis

Drilling an oil well or most other types of drilling or coring is no longer a simple and uncomplicated operation. Drilling today at depths which exceed 9144 m (30,000 ft) is hazardous and requires personnel with long and varied experience in drilling. It also requires extensive experience and knowledge in the use of materials which are added to the drilling fluid or "mud," more often than not materials utilizing an industrial mineral. The drilling fluid can vary from a simple mixture of water and "mud" to a very sophisticated, scientifically compounded drilling fluid. Industrial Minerals Used in Drilling Fluids Industrial minerals which are commonly used in oilwell drilling and completion are listed in Table 1. The most important minerals, determined by sales, are bentonite and barite. The other minerals listed are either used to achieve a specific purpose or are used regularly but in limited quantities. The main suppliers of drilling fluids internationally are Magcobar Div., Dresser Industries, Inc.; Baroid Div., National Lead Co.; IMC Drilling Mud Co., (a subsidiary of international Minerals and Chemicals Corp. and Halliburton Co.); and Milchem, a division of Baker Industries. Most of the industrial minerals are found in North America, with barite mines and processing plants located in Nevada, Arkansas, Missouri, and Arizona, and bentonite mines near Graybull, WY. Other mines, such as those in Nova Scotia, are capable of shipping to South America and to the European and Middle East countries. Most of the materials processed by any of the suppliers must conform to specifications set by the American Petroleum Institute (API) or the Oil Companies Material Organization (OCMA). These specifications provide for uniform physical and chemical properties of the materials to be sold on the open market. Function of Drilling Fluids In the early days of rotary drilling, the primary function of drilling fluids was to bring the cuttings from the bottom of the hole to the surface. Today it is recognized the drilling fluid has at least ten important functions: 1) To remove the cuttings from the bottom of the hole and carry them to the surface. 2) To cool and lubricate the drill string and drill bit. 3) To build an impermeable cake on the wall of the hole. 4) To control subsurface pressures. 5) To hold cuttings and weight material in suspension when circulation is interrupted. 6) To release sand and cuttings at the surface. 7) To support part of the weight of drill pipe and casing. 8) To reduce to a minimum any adverse effects upon the formation adjacent to the hole. 9) To insure maximum information about the formation penetrated. 10) To transmit hydraulic horsepower to the bit. In order to accomplish some or all of these functions while penetrating formations of various characteristics, several types of drilling fluids systems have been designed. Types of Drilling Muds There are two basic drilling fluid systems-water-base muds and oil-base muds. There is a wide variety of groups within these two main

Jan 1, 1983

By Charles W. Merrill

IF we follow the threads of the mining problems, upon which I have touched, we find them all leading to one great fundamental desideratum. The people of this State, of this Nation, and of this world must be brought to a better understanding of the basic nature of our industry-must be made more mineral-minded. It is my belief 'that there is not a man present among this earnest gathering of those interested in the mining industry, who has not a deep-seated and heartfelt desire that the existing unprecedented welfare and prosperity of the whole mass of American people be maintained not merely through our own generation but through the generations of our children and their children. In the decades to come there can be no question of the keenness of the foreign competition which we are doomed to meet, and in this great international contest that Nation which has the best balanced program of development and that broadness of vision in its governmental direction, which recognizes the necessity of a sympathetic attitude toward the upbuilding of such a broad pro- gram will be the Nation which will maintain and pre- serve that welfare of all of its people.

Jan 1, 1929

T. Kirke Rose, London, Eng. (communication to the Secretary*) :—The authors have shown that, under certain conditions, the rate of dissolution of gold by chlorine and bromine is reduced by the addition of 10 per cent. of silver to the gold, and that the action is almost stopped when the silver amounts to 30 or 40 per cent. of the alloy. Even if full recognition is given to the practical way in which the work was done, however, it is to be regretted that Prof. Hofman and Mr. Magnusou did not determine the temperature at which the experiments were carried out. From the details given, it may be inferred that the temperature was raised by chemical action by about 20' C. when 21 g. of sulphuric acid was added, and that the mixture was then slowly cooled down during the experiment. When bromine or very weak chlorine solutions were used, there could not have been any perceptible heating-action. As the action of both chlorine and bromine is aided by heat, it follows that the stronger solutions of chlorine were given an unfair advantage over the weaker solutions, and over bromine. If the temperature had been the same in each case, I do not think that the conclusions deduced by Prof. Hofman and Mr. Magnuson' would have been found to be justified. (This is speaking generally. In barrel-treatment the conditions are similar to those in the experiments.) The superior speed of bromine as compared with chlorine at equivalent strengths is not yet disproved, and the differences noted between strong and weak solutions of chlorine may have been largely a function of the temperature. Moreover, the authors used somewhat-coarse particles of gold, and did not try how far time was a factor, although it is obvi-

Jan 1, 1906

By G. G. Gunther, C. L. Boeke

(Any discussion resulting from presentation at the Los Angeles Extractive Metallurgy Division Meeting will appear in the November 1953 issue.) I. M. Symonds (Cia Minera de Penoles, Monterrey, N. L., Mexico)—This is a most interesting paper describing zinc deleading operations. Mr. Gunther was kind enough to show me his operation last fall. Outside of the excellent results, I was most impressed by the ease of control. I had expected a difficult operation requiring careful control and supervision, but found one requiring little attention. The only disappointing fact of the separation is the poor copper recovery in the concentrate of the deleading float. The final zinc concentrate still has about 3 pct chalcopyrite (assuming the copper is chalcopy-rite) which adversely affects the zinc grade. If the copper mineral is free, the poor recovery is probably due to the high cyanide concentration. Fortunately, about 75 pct of the copper is recovered before the pulp goes to the zinc circuit. Mr. Gunther's remarks about proper cyanide to zinc sulphate ratios cannot be overemphasized. Although our experience has been mostly confined to the conventional Pb-Zn separation, we have found these ratios most important, and more important in the mill than in the laboratory. The laboratory appears to give optimum results over a wider range of reagent control than the mill, especially in regard to the effect of cyanide. In the mill in handling relatively high grade ores, we usually find that ratios of cyanide to zinc sulphate of 1 to 10 or 20 or higher work best. Where there is a substantial amount of chalcopyrite present, it has been noted that cyanide in the range of 0.02 to 0.10 lb per ton of ore is often beneficial in zinc rejection and possibly in copper recovery in the lead concentrate, while larger amounts, say 0.20 to 0.25 lb per ton, will float more zinc and cause a serious rejection of chalcopyrite. On an ore with 15 to 20 pct Zn content, we have had to use 0.8 to 1.2 lb of zinc sulphate per ton of ore with the above cyanide to obtain optimum results. Sometime ago we made a laboratory study following Parral and Santa Barbara practice on an ore which never had a very satisfactory rejection of zinc in the lead concentrate. The results were not encouraging and a mill test was not run. Since then the study has been reopened using fresh zinc concentrate from the mill in the laboratory instead of one made in the laboratory. A reasonably clean lead float from the zinc concentrate was obtained. It has been checked several times and each time the zinc concentrate made in the mill responds and the one made in the laboratory does not. Although undoubtedly some reasonable explanations can be given, it is presented here only

Jan 1, 1953

By H. Landsberg

THE curriculum presented here is an outgrowth of discussions by the Committee on Geophysics Courses of the A.I.M.E. in previous years. It had to be a compromise between the desires voiced by employers of geophysicists, professional geophysicists and the possibilities at an average college. There one has to face the questions of the available teaching staff, the inertia of administrators and teachers set in their ways, and the red tape involved in modernizing antiquated curricula. It is, of course, not ideal to have colleges and universities lag 10 years behind the times. Rather, instead of being prodded by industry, -they should be ahead of industrial needs. There should also be a certain amount of leeway for the student in any college curriculum. All these points had to be considered in drawing up a curriculum, which, instead of being narrowly termed "geology" or "geophysics" was rather called "earth science." It gives the student a chance to specialize in one of the various branches represented by teachers on the faculty of The Pennsylvania State College, giving as options Geology (with subdivisions of Mineralogy and Paleontology), Geophysics, Geography, and Meteorology. Table IA. represents the option of geophysics in the curriculum that envisages that a student may want to make his career in any of the fields encompassed by the American Geophysical Union or in geoexploration. This is, of course, only the start of an education that in most cases will have to be followed by graduate work for complete professional training. The outlined curriculum is definitely of an engineering type and is identical for all of the four options mentioned for the first two years. Specialization will start in the junior year but even thereafter the branches are kept as closely allied as feasible in order to permit a student to change from one to the other (e.g., because of a different aspect in the employment situation) with a minimum of additional work. Table IB shows the geophysics option according to subject matter, indicating the considerable amount of work in the fundamentals of mathematics, physics and chemistry with a liberal number of geology courses, and some engineering. The courses in the field of geophysics are limited-just two lecture courses as a general introduction and one field course, to permit the student a visualization of the correlation between mathematically analyzed physical data and the geological realities. Thesis work is considered essential to teach the student, while he is still in college, some things S. F. Kelly has mentioned as desirable: (I) following of instructions for somewhat independent work; (2) organizing of material, and (3) producing a readable report. This, together with the personal contact with the advising faculty member, will help in forming a student's personality. The seminar course attempts to get the student into the habit of reading current literature, so that he can keep abreast of the times.

Jan 1, 1941

By Nathaniel Arbiter

T. M. Morris (School of Mines and Metallurgy, Rolla, Mo.)—Rate studies promise to help quantify flotation operations. The author's exposition of rate studies is therefore laudable. However his exposition of a second order rate equation rather than a first order rate equation is not convincing. It is important to use the correct equation, otherwise erroneous conclusions may be drawn. The data assembled by the author and plotted according to a second order rate equation can be plotted according to a first order rate equation. As a matter of fact much of the data used reveals that a second order rate equation is not applicable. According to the method used by the author for plotting data, the reciprocal of the slope of the line is the maximum possible recovery. Physically this cannot exceed 100 pct, yet several graphs yield maximum recoveries greater than 100 pct. For example: l—Curve 2, Fig. 1 yields a value of 120 pct; 2—Curve 2, Fig. 2 yields a value of 115 pct; 3—Fig. 7 yields a value of 110 pct. The real test of the graphical method is, as the author points out, whether or not the earliest points agree with a straight line. The second order rate plot does not fulfill this requirement. Fig. 10 shows the data used by the author to obtain Curve 2 in Fig. 1, plotted according to both a second and first order rate equation. Fig. 11 shows the two rate plots made from data published by Ludt and DeWitt.19 In Fig. 10 the first order rate plot gives a very good fit and obeys the boundary condition of passing through the origin. For the second order rate plot a straight line can be drawn through the last three points but the earliest points are not in agreement with this line. The reciprocal of the slope of the straight line gives a value of maximum possible recovery of 112 pct. The maximum possible recovery according to the first order rate plot is 78 pct. In Fig. 11 the first order rate plot again fits all of the points very well and passes through the origin. The second order rate plot shows wide deviation of the earliest point, indicating that the second order rate equation is not applicable. The reason for the fit of data to the second order rate equation during longer flotation times is that R, the cumulative percent recovery, changes slowly toward the end of the flotation operation, so that when t/R is plotted against time, one is, in effect plotting t against t and one would certainly expect a straight line. The author attempts to show that the second order rate equation is correct by citing evidence which shows that recovery is a function of initial concentration. This is a debatable point especially since, in the author's original presentation of this paper at the St. Louis

Jan 1, 1952

By AIME AIME

A CORPORATION would go into bankruptcy if its affairs were conducted as are those of the state of New York, according to the Committee on New York State Government Reorganization of the American Engineering Council of the Federated American Engineering Societies, in a report to the chairman, of the Joint Judiciary Committees of the Senate and Assembly. The report, just made public, was signed by the three members of the committee who were appointed by Herbert Hoover. They were H. de-B. Parsons, chair- man, Paul G. Brown and Lewis B. Stillwell. Although the American Engineering Council is a national organization, it decided to aid in governmental reorganization in New York State because of the magnitude of the task. The Council's committee in its report urged the passage of three state reorganization amendments for consolidation of departments, an executive budget system, and a four-year term for the higher state officials. In the words of the report :

Jan 1, 1921

By J. C. M. Li

A dislocation model is constructed for a cylindrical tilt boundary of which the axis of tilt is parallel to the axis of the cylinder. The strain energy per unit area calculated from this model agrees with thut of an infinite vertical wall of edge dislocations. Based on this model, a dislocation mechanism for the shrinking of such a cylindrical boundary is proposed. The power relation between the grain boundary velocity and the driving force is accounted fm by the stress dependence of dislocation velocity. The activation area for grain boundary motion is found to correlate with that .for Creep in aluminum. In the preceding paper' the velocity of a curved grain boundary is found to be a power function of the driving force, [1] where M is the velocity at unit driving force, y is the grain boundary energy, and p is the radius of curvature. This finding adds another nonlinear rate equation to metallurgical phenomena. While a macroscopic theory for the steady state as just presented2 can be used to understand the shape of the moving boundary, such theory usually does not provide any information about the atomistics of the process. It is attempted in this paper to discuss the nonlinear rate equation in terms of a dislocation mechanism. A DISLOCATION MODEL FOR A CYLINDRICAL TILT BOUNDARY Before a dislocation mechanism can be proposed for the motion of a cylindrical tilt boundary, it is necessary to construct a dislocation model for the boundary. For simplicity, a tilt boundary in a simple cubic lattice will be examined. Although this does not represent the situation in aluminum, it is expected that the general features will be similar. The details of the model in the fcc lattice can be constructed when a refinement of the simple model is called for. A cylindrical low angle tilt boundary in a simple cubic lattice is shown in Fig. 1. Two sets of edge dislocations are needed as shown. A schematic representation is shown in Fig. 2(a). In terms of a continuous distribution of dislocations, the density of dislocations n, of Burgers vector b, in the small segment ds of the grain boundary is Similarly the density of dislocations n, of Burgers vector bz in the same segment ds is where is the tilt angle of the grain boundary. Based on this continuous distribution of dislocations in the grain boundary, it can be shown that the interaction between a small segment of the boundary and the rest of it is zero. Furthermore, the stress produced at any point inside or outside the cylinder is also zero. This shows that the model is acceptable in the sense that the boundary has no long-range stresses. Since the model of continuous distribution of dislocations in the grain boundary does not reveal the interactions among individual dislocations, a discrete dislocation model has to be used for such purpose. For simplicity, an equivalent model is shown in Fig. 3. This arises because the total Burgers vector is, from

Jan 1, 1970

By L. H. Reiss, J. Groult, L. Montadert

Many fields, where the reservoir is composed of sandy layers, show great complexity because of the lack of continuity which results from a particular type of seditnentation. This complexity may be a factor of prime importance in studying reservoir drainage, especially in the displacement of oil by water or gas. This paper describes work done to study this heterogeneity and its influence in the exploitation of the fields of the lower Devonian sandy shale in the Fort Polignac Basin in Algeria. Two lines of research were followed. 1. On the border of the hasin, a detailed sedimentological study established rules for the distribution of the sandy zones, which furnished hypotheses necessary for devising a geologic model of the reservoir. A certain number of sandy zones were recognized and characterized by their sedimentation. 2. In the interior of the basin, production logs deterrnined the productivity profile. Study of these point data led to a description of the distribution of oil and gas phases in the reservoir so that the continuity of different zones between the wells could be deduced. These techniques were applied to the study of the lower Devonian sandy shale reservoir of Zarzaitine. The sedimentological study guiding the correlation work, with the aid of the conventional static data (logs and cores), led to the establishment of a useful geologic model of the reservoir. Production logs, thanks to the contribution of dynamic elements, permitted corrobora-tion of the model. In particular, the logs confirmed separation, as proposed by the sedimenfological study, of two comparable sandy groups by revealing the continuity of a thin impermeable layer, invisible on conventional logs. INTRODUCTION The heterogeneity of sandstone reservoirs considerably influences the distribution of fluids, as well as their displacement in the reservoir. Rational development of a field and maximum recovery of hydrocarbons are closely tied to an exact and precise knowledge of the intern architecture. We will try to show how it is possible I refine the knowledge of the reservoir by seeking qui different and varied sources of information. Productic geology, the group of techniques which leads to idei concerning reservoir architecture and its geometric descris tion, furnishes the framework of this undertaking. Of these techniques. those used so far are qui varied. Descriptive as well as quantitative, the technique partake as much of classical geology as of reservo science. They include (1) geologic studies of the enti basin, especially a stratigraphic and sedimentologic study of the reservoir member at its outcrop, detail1 observations of cores taken from wells and, finall oriented cores; (2) interpretation of geophysical dat (3) interpretation of electric logs, nuclear and sonic lo and dipmeters: (4) petrophysical study of the reserve on samples taken from wells; (5) reservoir dynamics (stu of the production history and, in particular, interpretati of production logs); and (6) analysis of the fluids a thermodynamic studies. This incomplete list could also include (1) study the migration of the fluids, (2) geochemistry (chemi characterization of the oils), (3) regional hydrodynamii and (4) injection and detection of tracers. If most of these techniques are classic, attention i nevertheless be called to applying two of the techniql in conjunction: the study of the reservoir member its outcrop and the study of dynamic distribution fluid phases in the reservoir through use of product logs, used in the study of the sandy shale reservoirs the lower Devonian of the Fort Polignac Basin, Alge in particular, their application to the study of the 2 zaitine field where they have led to a new and satisfact model of the reservoir will be described. THE ZARZAITlNE FIELD Situated in the interior of the Fort Polignac 8 about 150 kilometers (km) north of the lower Devol outcrop, the Zarzaitine Devonian oil field was discovc On Ian. 28, 19'' (Figs. 1 and l8). It is in the fern a monocline truncated by two perpendicular fault: great throw, with a downthrown section to the north\: Erosion at the top of the structure has caused one of it to disappear. It is a reservoir with a gas cap an m coefficient on the order of 1:5, open to the aql On the northeast, with the oil zone covering an Of 106 sq km and with initial oil reserves of 222 mi

Jan 1, 1967

By F. M. Smith, R. H. Moore, J. R. Morrey

Electrodiffusion in y cerium reported by Henrie has been confirmed and a Preliminary estimate made of the relative rates of electrodiffusion of iron, cobalt, and nickel. These diffuse to the anode at rates decreasing in that order. In addition, copper and manganese exhibit slow, but detectable, diffusion to the anode and molybdenum exhibits detectable diffusion to the cathode. The electrodiffusion of carbon, .zirconium, antimony, magnesium , and silicon in y cerium could not be detected. Iron and cobalt diffuse in y cerium at rates proportional to the current density and with no apparent dependence on temperature. Decreasing polarization of iron and cobalt with increasing temperature, which cancels the expected rate increase, would account for this behavior. The electrodiffusion rate of iron in y uranium and in E plutonium has been measured. Diffusion of iron is anode-directed. Tin was found to diffuse to the cathode, in y uranium, at an appreciable rate. In all of these solvent metals, negative ions diffuse to the anode and positive ions to the cathode. The potential field effect appears to account satisfactorily for these results. FROM early experimental work summarized by Jost1 and Seith,2 the driving force for electrodiffusion was attributed to the potential field acting on ions in a metal. More recently, Heuman,3 Wever,4 and Huntington5 have shown that momentum interchange between conduction electrons and mobile entities in the metal contributes to electrodiffusion. Electron momentum interchange is anodically directed and the direction of diffusion resulting from the field force is dependent upon the charge on the diffusing entity. These two effects may either reinforce or oppose each other. Glinchuk6 has pointed out that momentum transfer in defect conductors should be cathode-directed and this appears to be the case as demonstrated by wever's4 work on iron. Barnett's7 work, on the other hand, indicates that, even in defect conductors, electrons show a negative E/m ratio when accelerated with respect to the lattice and should lead to anode-directed momentum transfer. In discussing this problem, Wever and seith8 suggest that defect electrons interact preferentially with activated ions so as to allow a net movement toward the cathode while still maintaining an electron momentum transfer in the anode direction. Williams and Huffine9 and Henriel0 have demonstrated that electrodiffusion may be useful for purification of yttrium and cerium. In yttrium, Williams and Huffine note that movement of several metallic impurities toward the anode is in keeping with observations in most other metallic systems and indicates that yttrium remains a normal electronic conductor at least to 1230°C. Close inspection of their data shows, however, that oxygen, nitrogen, and the transition elements diffused toward the anode, while nontransition elements diffused toward the cathode. This suggests that potential field effects may have been appreciable. The present work was concerned with the applicability of electrodiffusion as a technique for purification of plutonium, but, because of the obvious hazard inherent in work with this metal, experiments to develop the technique were carried out using cerium and uranium. The results of electrodiffusion measurements on these metals and on plutonium are reported here. EXPERIMENTAL The metal specimens prepared for this work were 6 in. long, 1/4 to 1/2 in. wide, and 1/16 to 3/32 in. thick. The uranium specimens were machined from a bar which analyzed 310 ppm Fe and the electrodiffusion of iron was followed by spectrographic and by chemical analysis. Cerium and plutonium specimens were cut from sheet rolled from ingots obtained from molten salt-metal equilibrations during which radioactive tracers were introduced. The electrodiffusion of the tracers was subsequently determined by counting methods. The specimens were electrolyzed between nickel electrodes containing resistance heaters used to equalize the specimen and electrode temperatures, thereby reducing thermal gradients. The temperature of the electrodes adjacent to the ends of the specimen was measured with chromel-alumel thermocouples which were connected to the heater controls. The surface temperature of the specimen at a point midway between the electrodes was measured with a sapphire rod pyrometer, the output of which controlled the dc power supply. This assembly was enclosed within an evacuable chamber containing a quartz viewing window. The temperature of the specimen over its entire length could be scanned with a portable pyrometer through

Jan 1, 1965

By Barry D. Lichter, Pierre Sommelet

High-temperature heat contents of InSb, GaSb, and AlSb were measured over the temperature range 400" to 1450°K using a diphenyl ether drop calorimeter. Smoothed ualues of the thermal properties, H$ - H:9s, have been derived and are tabulated at even temperature intervals. The heats of fusion of the three compounds were determined as, respectively, 5707 *100, 7780 * 100, and 9800 5 3011 cal per g-atorn at the determined melting points of 797" l°, 985" * , and 1330" * 5°K. The calculated entropies of fusion are, respectively, 7.16 0.12, 7.90 * 0.11, and 7.37 * 0.23 cal per deg per g-atotn. The heat capacities increase substantially on tnelting in contrast to the behauior of structurally related germanium and silicon. Deriations from the Kopp-Neumann rule are negative for solid compounds and positive for the liquid phases. Previously obsevrrd "post melting" in InSb is confirmed. The high-temperature thermal properties of 111-V compounds are presently not well-established, despite the technical importance of these semiconducting cbmpounds. Uncertainties in available heats of fusion and heat contents have seriously hampered thermo-chemical evaluations' and thermodynamic analyses of phase equilibria2"" in these systems. This paper reports results of high-temperature heat content investigations of InSb, GaSb, and AlSb measured in the range 400" to 1450°K employing a diphenyl ether drop calorimeter. Similar measurements for InAs and GaAs will be reported in a following publication.~ EXPERIMENTAL PROCEDURES Samples. High-purity samples of the compounds InSb and GaSb were supplied in the form of crushed crystal fragments by Dr. Carl Thurmond of the Bell Telephone Laboratories and in the form of single crystals by Dr. A. Strauss of the M.I.T. Lincoln Laboratory. Single-crystal samples of semiconductor-grade AlSb were supplied by Dr. W. P. Allred of the Bell and Howell Research Center. Chemical analyses indicated that all compounds were stoichiometric to *0.1 at. pct, which is within the experimental uncertainties of the analyses. Samples were crushed, weighed, and encapsulated in evacuated, thin-walled, fused silica capsules. The capsules were nearly identical in external shape, 2 cm by 2 cm diam, but varied in weight due to differences in wall thickness. One sample of AlSb was contained in a thin-walled, high-purity alumina cup encapsulated in silica and used for heat content determinations of liquid AlSb. The capsule materials showed no visual evidence of reaction with any of the compounds. The sample and capsule weights are given in Table I. Calorimeter. A Bunsen-type calorimeter, similar in design to a previously described instrument6 but employing diphenyl ether (C6H5)'0 as the calorimetric substance, was used for measurements of heat contents above 300.0°K, the melting point of diphenyl ether. Heat input to the calorimeter caused isothermal melting of diphenyl ether, and the resulting increase in volume was measured by displacement of mercury from the calorimeter into a 200 cm horizontal, calibrated capillary, 1.25 * 0.01 mm diam, or into a weighed beaker. The advantages of diphenyl ether over water have been previously pointed out7 and include: i) an increase by a factor of 3.5 in sensitivity as measured by the ratio of the volume change to the enthalpy change on fusion, ii) the smaller required extrapolation from the melting point to the standard temperature of 298.17"K, and iii) the positive volume change on fusion of diphenyl ether in contrast to the contraction which occurs on fusion of ice. Diphenyl ether was purified by fractional crystallization to 99.95 mol pct as determined from the melting point depression with fraction crystallized. During assembly of the calorimeter, the ether was repeatedly outgassed under high vacuum to remove dissolved air. The calorimeter receiving vessel consisted of an 8-in.-long by 1:-in.-diam copper tube with twelve horizontal 3-in.-diam radiator "fins" for dissipating heat to the surrounding mantle of diphenyl ether. Before forming the mantle the chamber surrounding the receiving vessel contained 3300 cu cm of liquid diphenyl ether above 250 cu cm of mercury which was

Jan 1, 1970

By Elmars Ence, Harold Margolin

A. J. Goldak and J. Gordon Parr (University of Alberta) —While we appreciate the difficulties involved in any investigation of this system, and we wish to congratulate the authors on their comprehensive efforts, there are several aspects of their paper that are not clear to us. 1) If the 6 phase is, in fact, isomorphous with Ti3Sn, it should not be designated Ti,Al. An 4B structure cannot be isomorphous with an ordered structure of the DO type. Anderko et al.' suggested that the structure be called Ti3A1, and we believe this to be a more reasonable designation. The confusion is compounded when the authors designate the phase Ti3Al—yet the composition limits of this phase (according to their diagram) are approximately Ti,A1 and Ti,Al. Further, while Pietro-kowsky is said to have pointed out that the structure of the 6 phase is isomorphous with Ti3Sn, we understand that this was only a suggestion that was not confirmed. Margolin and Ence do not appear to have presented any evidence to support the suggested isomorphism. 2) In referring to the precipitation observed microscopically during the initial breakdown of high A1 a during quenching, the authors state that "such precipitation is not likely to be detected by Debye-Scherrer techniques". We suspect that if the precipitate was visible by optical microscopy, it must have at least one dimension of the order of 1 or greater, and would therefore be readily detected by diffraction techniques. 3) The authors state: "The basis for this suggestion (that 6 forms peritectically P + L—6) is the observation that the ,'3 + 6 and 6 phase fields were

Jan 1, 1962

By AIME AIME

THE No. 9 mine of the Wheeling & Lake Erie Coal Mining Co., a subsidiary of M. A. Hanna & Co., at Fairpoint, Ohio, has normally produced about 1000 tons of coal daily for several years, but recently it was converted into an experimental mine to afford means of studying new methods and equipment under consideration for development and mining. Among other projects, the possibility of using a duck-bill, self- loading conveyor in driving entries, with a view of in- creasing the rate of progress where quick development is of importance was studied. Actual operation soon revealed that even though break-throughs are made ,every 60 ft., as required by the state mining laws, the :amount of natural Ventilation reaching the working face was not sufficient to supply the men and that in ,order to obtain a plentiful supply of pure. air and maximum efficiency and to avoid costly interruptions after shots, it was necessary to supply auxiliary ventilation by using Ventube and a Vano fan.

Jan 1, 1929

By W. C. Hagel, H. J. Beattie

Variations in the secondary phase reactions of six nickel-and cobalt-base alloys were determined as a function of solu-tioning from 1700" to 2200°F and aging at 1200" to 1800° F for times up to 1000 hr. Room-temperature impact energies and hardnesses were also measured. Precipitation hardening of these alloys results mainly from the grain-interior formation of ? '; M23C6 appears principally as grazn-boundary cells which can be eliminated by intermediate high-temperature aging treatments. Cellular precipitation of ?' occurs up to 1500°F in cobalt-nickel alloys devoid of chromium, where precipitation by this mode can be attributed to a large degree of lattice disvegistery. THE usefulness of nickel- and cobalt-base alloys is dependent on balancing the strength and ductility provided by the solid-solution matrix, dislocation-type subboundaries, grain-boundary phases and genera1 precipitation within individual grains. Since equilibrium relationships for complex austenitic alloys are not easily fixed, a satisfactory balance

Jan 1, 1960

By A. T. Janssen

Production planning of direct-shipping ore from a number of relatively small deposits serves to sequence development and mining of these deposits so that both long- and short-range demand can be met while the timing of development cost is such that the average annual rate is minimized. Hand-computed methods have the disadvantage that they require substantial effort and time and cannot be exhaustive. The application of operations research and computers not only overcomes these disadvantages, but opens up additional applications, such as feasibility studies involving alternative mining strategies and changes in the ore market. The method employed concerns linear programming and specifically the Big-M algorithm applied to the variant on the simplex technique with penalties applied to deviations from the desired ore grade. Acceptable 20-year production schedules could be generated in relatively little time, i. e. , in less than 200 seconds for the central processor of the Control Data Corporation 6400 system of the University of Colorado in Boulder.

Jan 1, 1969

The following list comprises the names of those persons who became members during the period of Mar. 10, 1918, to Apr. 10, 1918. ADAMS, NOAH- :.. Geol.,. E. N. Gillespie & Co., Box 1875, Tulsa, Okla. ALVAREZ, PEDRO Asst. Met., American Smelt. & Refin. Co., Blue Hill, Maine. BARTRAM, JOHN G., Pet. Geol., Roxana Petroleum Co. of Oklahoma, Cheyenne, Wyo. CHANEY, S. E Supt.., Arizona Binghamton Copper Co., Stoddard, Ariz. CLEVELAND, EARL C Mgr., Deadwood Min. Co., Mogollon, N. M. DENNIS, HOWARD B Min. Engr., Empire Mines, Grass Valley, Cal. FOWLER, ARTHUR A., Partner, Rogers, Brown &- Co., 30 Church St., New York, N. Y. FRIEDMAN, L. A Pres. and Gen'l Mgr., Rochester Mines Co., Lovelock, Nev. GUIBERSON, S. ALLEN, JR 923-24 1. N. Van Nuys Bldg., Los Angeles, Cal. KROHN, ARTHUR Mine Supt., Missouri Metal Corpn., Mine La Motte, Mo. KURSELL, H. A., Mgr., Altai Mines Ltd., Zmeinogorsk, Altai Gov't, Siberia, Russia. LANE, L. RAY Mine Examinations, Galiano 24, Aptd. 1066, Havana, Cuba.

Jan 5, 1918

NEW MEMBERS The following list comprises the names of those persons who became members during the period of Oct. 10, 1917, to Nov. 10, 1917. ABEY, HIROSHI Min. & Met. Engr.. Mitsubishi Co., Tokio, Japan. BARNETT, WALTER W., Assayer & Chem., Seoul Min. Co., Tul Mi Chung, Chosen, Korea. BATES, WILLIAM S Min. Engr., Anaconda Copper Min. Co., Butte, Mont. BENDELARI, ARTHUR E Mgr. of Mines, Eagle Picher Lead Co., Picher, Okla. BERKEFELD, PAUL C Mining Engr., 2901 Piedmont Ave., Berkeley, Cal. BILLINGS, It. S Mgr., Sheep Trail Pyramid Mines Co., Kingman, Ariz. BILLWILLER, C. J., JR Mgr. Nitrate Agencies, Ltd., Iquique, Chile. BLUM, EDWARD H., Engr., Asst., to Pres., The Atlantic Refining Co., 3144 Passyunk Ave., Philadelphia, Pa. BORDEN, GAIL, Vice-Pres. & Treas., American Safety Explosive Co., 50 East 42d St., New York, N. Y. BRESLIN, THOMAS F Min. Engr., Cebu, Cebu, P. I. BURKE, JAMES M., Efficiency Engr., Calumet & Hecla Mining Co., Calumet, Mich. CANTON, WILLIAM R Met., Nevada Consolidated Copper Co., McGill, Nev.

Jan 12, 1917