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By Herbert W. Huse

Nitrogen, and its compounds, unique among the materials described in this volume, is absolutely essential to the existence of the human race. Almost all minerals are important and the absence of any one of them would be sorely felt; but nitrogen is an integral part of the cycle of life itself. Man cannot live without nitrogen which, as an inert gas, composes the major part of the air he breathes; as compounds, nourishes the vegetation which he eats; and, as protein, forms a part of his very flesh and blood. Nature originally provided man with a vast reserve of usable nitrogen compounds in the form of fertile soil. She constantly replenishes the supply by "fixing" nitrogen in the air at the estimated rate of 400,000,000 tons per year (an insignificant 6 lb per acre) during electrical storms. She has also placed certain microorganisms in the soil which are able to "fix" nitrogen and convert it into forms which plants can use. Legumes like cow peas, soy beans, clover, and alfalfa have extraordinary roots which serve as stimulating hosts to these bacteria which, in turn, nourish the plant. By plowing in all or part of such crops, their above-average nitrogen content can be returned to the soil for other more useful crops. The mechanism for this recycle is supplied by "denitrifying" bacteria which attack the dead plant tissue and liberate nitrogen and ammonia. However, since one crop of grain, sugar beets, potatoes, tomatoes, etc., takes out a major portion of the nitrogen which a plowed-in legume crop can supply, this method of fertilization is obviously inadequate. Drastic intervention by man has become necessary to support the ever-growing population of the world.9,15,20 Old civilizations with a high population density, such as the Chinese, were able to exist for centuries by carefully tilling the soil, rotating crops, and returning to the soil all the nitrogen in vegetable wastes plus human and animal excreta. But the lack of a means for augmenting their supply of nitrogen placed a ceiling on further development and kept the mass of the population in a chronic state of undernourishment, frequently punctuated by famine. Nitrogen plays another important role in the life of mankind. In the form of explosives, nitrogen helps to wrest from the earth many materials needed for our material well-being. Also, in the form of explosives and propellants, nitrogen increased the destructiveness of wars to a point only exceeded by the fantastic power of atomic energy. Man's first really effective efforts to improve his position with respect to nitrogen began in the 18th Century with the mining of sodium nitrate. By the late 1880's this had become a big industry serving a large part of the world. In the late 1890's nitrogen, in the form of ammonia, was being recovered from coke-oven operations. In 1900 nitrogen, in the form of nitric oxide, was being obtained from the air by an electric-arc process. About 1904 another "fixation" process based on the reaction of nitrogen with calcium carbide to form cyanamide was commercialized. By 1913 the Haber-Bosch process of "fixing" atmospheric nitrogen by reacting it with hydrogen to produce synthetic ammonia was successfully applied on a large scale, first in Germany and then throughout the industrial areas of the world.9 All the above methods of obtaining nitrogen compounds are still in use and, between them, they assure mankind of adequate supplies for all time. While this fortunate situation is not unique amongst industrial raw materials, all too few of man's needs are so well in hand.

Jan 1, 1960

By S. W. Parr

STUDIES relating to the behavior of coal toward oxygen may have for their purpose the determination of the fundamental factors that underlie spontaneous combustion, weathering and deterioration, and the general topic of storage, as well as those properties that have to do with the underlying principles of carbonization. There is also involved the possibility of developing information relating to the constitution of coal, or at least the chemical properties inherent in the type substances of which the coal is composed. It is the purpose here to record certain FIG. 1. results bearing on this latter idea of the chemical properties that characterize the main constituents of bituminous coal. The avidity of freshly mined coal for oxygen has long been known. What happens to the coal or to the oxygen is not so clear. Is the oxygen absorbed or chemically combined, and what are the conditions as to time, temperature, texture, or components that are most involved in the phenomenon?

Jan 6, 1925

By J. B. Dilworth

In estimating the investment-value of a mining-property or plant, the value of which decreases with operation, it is often necessary to know the sum which must be set aside periodically from earnings either to renew the plant at the end of its life, or to return the capital involved when the earningpower of the investment has ceased. In such cases it is manifestly incorrect simply to divide the total amount to be retired by the 'number of periods (usually years) during which the investment shall be active, as the sums periodically withdrawn have a certain interest-earning power varying with the length of time they are held and with the opportunities afforded for their investment. But though the interest may be considered to accumulate regularly year by year, yet the rules and tables for compouiid interest do not apply, owing to the addition of a fixed amount of new money to the total at the beginning of each period. Briefly stated, the problem of sinking-funds is, to find the amount of money which must be periodically set aside at a certain rate of interest, regularly compounded, to yield a certain sum in a given length of time. In most practical cases the interest is compounded and the fresh amount added at the same time—usually once a year—and on this basis the problem may be solved as follows : Let S = total amount to be retired, Let T = interest rate : R = 1 + r, Let n = life of tlie sinking-fund or the amortization-period, Let L = the sum set aside at the end of each year. Then the amouilt of the sinking-fund at the end of first year is 2, which at the end of n years will have illcreased by compound interest to IRn-l. Similarly, another amount, x, will be set aside at the end of second year, which will in turn increase

Jan 1, 1911

By E. P. Palmatier

RECENTLY a cooling system has been in process of installation on the 3400 and 3600-ft. levels of the Magma copper mine at Superior, Ariz. The general system of ventilation employed at this inclined-vein mine is as follows: Ventilating air enters the shafts on the western side of the mine. Booster fans at each level each deliver approximately 38,000 cu. ft. per 'min. to the drifts. This air passes diagonally upward to the upper levels of the mine on the eastern side, where it passes up the shafts to large exhaust fans on the surface. Owing to the dip of the vein, all operations on the eastern side of the mine are above the 2500-ft. level, and those on the western side below the 2500-ft. level. At present, 2500 lineal feet of new drifts are being driven-on each of the 3400 and 3600 levels. The rock temperature is about 135°F. Until the new installation is completed, ventilating air for the two levels is supplied through Flexoid tubing from small booster fans -on the 3200-ft. level. The air picked up by these booster fans has a dry-bulb temperature of approximately 85°F. and a wet-bulb temperature of 82°F. By the time this air reaches the end of the Flexoid tubing at the 3600-ft. level, the dry-bulb rises to 101°F. and the wet-bulb to 86°F. The conditions at the head of the new drift were 102' dry-bulb and 93' wet-bulb.

Jan 1, 1937

By C. D. Starr

IT is well known that the martensite reaction can be induced to occur isothermally above the M, temperature by plastic deformation of an alloy in its austenitic state, and also that as the test temperature is increased above the M. temperature, plastic deformation under a given set of conditions merely causes additional slip with a corresponding tendency toward the formation of less martensite per unit of strain. Thus it appears that a maximum temperature exists above which martensite cannot be formed isothermally by plastic deformation. This temperature is commonly designated as the equilibrium temperature Te. Attempts to determine experimentally the equilibrium temperature have indicated that a critical temperature is observed, under a given set of conditions, above which martensite cannot be formed isothermally by plastic deformation. But the observation of a "so called" critical temperature, Te, should not be confused with the equilibrium temperature, Te. In order to clarify this anomaly, true stress-strain curves were obtained for a series of type 304 stainless steel specimens (manufacturer's analysis, 0.08 pct C, 18 to 20 pct Cr, 8 to 10 pct Ni, balance Fe) over the temperature range 67" to 300°K.' Since martensite is magnetic, a quantitative measure of the amount of martensite that was produced by plastic deformation was obtained by determining the magnetic permeability as a function of strain. The results of these tests are given in Fig. 1. They appear to indicate that a plastic critical point does exist at about 240°K for the stainless steel under investigation here. But that 240 °K is not the equilibrium temperature nor even a true plastic critical temperature can be seen from Fig. 2 wherein the permeability of the same material is shown to increase with cold rolling at 293 OK. Consequently the observation of a "so called" plastic critical temperature is dependent on the mode of deformation and has no theoretical significance. Acknowledgment This work was sponsored by the Office of Naval Research. Permission to publish this note is gratefully acknowledged.

Jan 1, 1954

By A. T. Corey, C. H. Rathjens

INTRODUCTION Although the oil industry has been aware of the directional variability of permeability in porous rock, the directional variability of relative permeability has been largely ignored. Yet it is apparent that such an effect must be present in a system in which the distribution of oil and gas within the porous matrix is controlled by capillary forces. It is easy to visualize a rock composed of layers of fine and coarse material such that gas flow across the bedding planes would take place only after the average oil saturation had been reduced to a very low value. The fine layers, because of their greater capillarity, would remain saturated and act as barriers to the flow of gas after the coarse layers had been desaturated. Flow of gas parallel to the bedding planes would obviously take place at a much greater liquid saturation. Without more complete information concerning the geology of a reservoir than is generally available, it is not possible to predict exactly how such phenomena would affect the over-all performance of an oil field. It is possible, however, to predict qualitatively the effect of stratification on relative permeability measurements made on laboratory cores. In this investigation the effect of stratification was studied analytically by assuming that two porous materials with different capillary pressure-desaturation curves (but identical relative permeability curves) were in contact and in capillary equilibrium. As a qualitative check on the analytical results, cores having various degrees of visible stratification were used for relative permeability measurements made with fluids flowing both parallel and perpendicular to the bedding planes. A quantitative check was considered impractical because of the difficulty of devising models in which two materials of predetermined properties could be joined without the plane of contact becoming a discontinuity. THEORETICAL CONSIDERATIONS AND ASSUMPTIONS The assumption of capillary equilibrium in an oil-gas system implies that the difference in pressure between oil and gas is everywhere the same. This means that the curvature of the interfaces must be everywhere the same in order to satisfy the equation where PC is the pressure difference between phases, y the interfacial tension and r, and r2 are the major and minor radii of curvature. Depending on the pore size distribution of coarse and fine layers, the volumetric percentages of oil and gas in these layers will differ when equilibrium exists. The exact relationship can only be determined by obtaining the complete capillary pressure-desaturation curves for each of the porous materials in contact. It has been pointed out elsewhere' that the capillary pressure-desaturation curves of sedimentary porous materials can often be approximated by the relation where C is a constant and Soe is the effective saturation to oil based on a percentage of the pore volume effective to flow. In the same paper it was indicated that, as a first approximation, the values of oil relative permeability are given by and the values of gas relative permeability by For this analysis Eqs. 2, 3, and 4 were assumed to apply to each of two components of a hypothetical porous rock in capillary equilibrium. It was also assumed that each of the components had a residual wetting phase saturation of 20 per cent so that 80 per cent of the total pore volume was effective to flow. The permeability of the coarse stratum was taken as 100, and its displacement pressure was such that C in Eq. 2 had the numerical value of 1. The corresponding values for the fine stratum were 10 for the permeability and 10 for C. Units are not specified because they do not enter into the final results. The choice of the permeabilities and displacement pressure ratios was made to expedite the calculations. Any reasonable rock properties could have been chosen without changing the results qualitatively. Several arrangements of the two components were studied. Table 1 summarizes the resultant permeabilities obtained for four types of arrangement. RELATIVE PERMEABILITY CALCULATIONS The first step in the computation of relative permeability for the composite cores was the plotting of the capillary pressure-desaturation curves and the relative permeability curves for the individual components according to Eqs. 2, 3, and 4. At arbitrary

Jan 1, 1957

By T. KIRKE ROSE

A Discussion of the paper by H. O. Hofman and M. G. Magnuson, read at the Lake Superior meeting, September, 1904. (British Columbia Meeting, July, 1905.) 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 re¬duced 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, how¬ever, it is to be regretted that Prof. Hofman and Mr. Magnuson 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 were 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 given oil p. 432 of the Bi-Monthly Bulletin, March, 1905, 1 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

Sep 1, 1905

By R. L. Fleischer, W. F. Hosford

Tensile data for coarse grained aluminum Polycrystals suggest that the "grain size" effect is not due to dislocations piled up at grain boundaries but rather is primarily a relative size effect due to surface crystals being weaker and less confined. STUDIES directed at interpreting hardening of poly-crystalline metals normally identify their strain hardening properties with those in some particular type of single crystal.1"4 The recent recognition in face centered-cubic metals of a nearly linear stage with rapid hardening occuring at comparable rates for both polycrystals and single crystals, suggested that the same process or processes determine both cases and hence that there exists some justification for the use of single crystals to understand polycrystals. Further evidence for the above view may be found by an approach initiated by Chalmers:5 By using bicrystals of controlled orientation it is possible to begin to assemble a polycrystal and also to study grain boundary effects in detail. In this way it has been found that a single grain boundary affects easy glide but not the subsequent stage II hardening.6 This result suggests that a sensitive way to observe grain boundary effects in polycrystals would be to vary grain size and measure easy glide. As will be seen, easy glide is only possible for coarse-grained samples, and hence the results will serve to fill in the gap in measurements between single crystals and bicrystals on one hand and fine-grained polycrystals on the other. One problem inherent in comparing single crystals with polycrystals is the uncertainty as to what slip systems are acting in a polycrystal. To compare the two types of samples, rates of shear hardeninn---L. on the acting -planes are needed. and these may be computed only if it is known what particular systems are active. The acting systems were examined for a coarse-grained polycrystal and it will be shown that the systems supplying the preponderance of slip can be determined with little ambiguity. EXPERIMENTAL PROCEDURE Twelve samples of aluminum were prepared by chill casting into a heated graphite mold, followed by annealing at 635° ± 5°C for 24 hr with an 8-hr fur- nace cool, and finally either etching7 or electropol-ishing.' The samples, with a 7 to 10 cm length between grips and 4.4 by 6.6 mm in cross section, were deformed at a strain rate of about 3 10 -3 . per min in a tensile device which has been described elsewhere.5 The composition was reported by Alcoa as 99.992 pct Al, 0.004 pct Zn, 0.002 pct Cu, 0.001 pct Fe, and 0.001 pct Si; nine samples were deformed while immersed in liquid helium and three in air at room temperature. The stress-strain curve for one of the samples (P-1) deformed at 4.2 "K has been reported previ~usl~.~ This sample was selected for determination of active slip systems. Eighteen of the crystals were examined by optical microscopy to determine the angles of slip line traces and by X-ray back reflection to determine orientation. By this means the slip planes were determined and the resolved shear stress factors for possible slip systems could be computed. Finally each sample was sectioned so that after etching, the number of crystals could be counted for each of ten newly exposed surfaces. The average of these ten values will be termed n, the number of crystals per cross section. Values of 11, varied from 1.9 (nearly bamboo structure) to 12.7. Sketches of typical cross sections appear in Fig. 1. RESULTS AND DISCUSSION: SLIP SYSTEMS 1) Determination of Acting Slip Planes—The stress axis orientation and operative slip planes in eighteen crystals of sample P-1, as determined by slip line traces and crystal orientation, are summarized in Fig. 2. For one of the crystals two planes had a common trace. so that the traces alone did not distinguish which plane or planes were slipping. However it was found that the stress resolving factor for the primary system was 0.386, .while that for the most stressed system in the other plane (indicated bv the dotted arrow) is 0.138. It will be assumed tgerefore that only the primary plane acted. Since the orientations were determined after extending the samples 4 pct, the stress axes may be rotated from their original value by as much as 2 deg in some cases. It is interesting to note that in five crystals only one slip plane acted, in eight two acted, and in five three planes were observed—an average of two slip

Jan 1, 1962

By Persifor Frazer

These properties, owned by Mr. William A. Butcher, of Philadelphia, are in the Panuco Mountain, which lies about thirty miles southwest of the town of Candela. It is a granite which penetrates the surrounding limestones and contains the famous copper-mine to which it gives its name. This mine, which is the property of a company in Philadelphia, has long been known to produce gold as well as copper from almost all its parts; and in corroboration of this be it said, that the undersigned has washed gold from a number of places where the works of the mine or natural sections had exposed the decomposed granite to view in the state of kaolin. It is well known that these junction- or contact-planes between two different formations are often the lodging-places of much freemilling gold, which through fissures are sometimes carried long distances perpendicular to the strata and into the interior of the formation. The structure of the Panuco Mountain, with its outlying spurs and adjacent foot-hills, forms a most instructive and unusual study. At a rough guess the area covered by this mountain will equal, perhaps, twenty-five to thirty square miles ; but its singular feature is the intimate welding together of two formations into one topographical unit. The lines of division between the granite and the calcareous sandstone are of such complicated character that they could not be mapped on a small scale. Unlike the majority of such contacts, the divisions between formations are not always marked in the Panuco Mountain by gulches, valleys, and streams (or the dry beds of the latter), but in the portion of the mountain which lies south of the Panuco copper mine, the lines of junction of these formations cross the gulches and promontories, and, in some instances, cannot be traced by any such topographical features. The house of the Panuco copper mine is 3742 feet above oceanlevel (by rough barometric observation), and the gold-mine about to be described is 235 feet above this, and about two miles distant,

Jan 1, 1886

By Kenneth Cottingham

The number of completions in 1944 in Ohio was only slightly greater than completions in the preceding year, but the initial daily volumes both of oil wells and gas wells declined considerably. The dry-hole ratio was a little lower than in 1943, even though in the year under review considerable effort was made to find new production. No new areas of consequence were discovered. Thirteen new gas pools, the largest of which was 1000 acres and the average 565 acres, were opened during the year. Eleven of these pools were in the Clinton sand, one was in the Oriskany, and one was in the Berea. Approximately 15 small pools might also be rated as discoveries, but because only one or two wells have thus far been completed in each, they cannot at present be properly evaluated. The latter pools average about 120 acres each. Some extensions were made to existing gas pools. The number of oil wells drilled was only one less than in 1943, yet compared with the year 1941, when twice as many oil wells were drilled, the difference is startling. Effective Aug. I, 1944, a blanket subsidy was granted of 35¢ per barrel on all Cleveland-Chatham, Coming, and Lima grades of oil, and 75¢ per barrel on Pennsylvania grade crude. The subsidy was authorized by the Office of Price Administration, with reimbursement to purchasers of the various grades made through the Defense Supplies Corporation, a branch of Reconstruction Finance Corporation. For several years the small operator, particularly the owner of stripper wells, was in a serious position. The subsidy has been a means of real help and, in addition to aiding the operator, it has prolonged the life of many small wells that otherwise would have been abandoned, with consequent loss of daily production and unre-covered reserves. It is questionable whether the price increase is sufficient to revive production of Corning grade, which has

Jan 1, 1945

By Thomas Read

SUMMARY THE cost of labor turnover in industry is so large as to justify the adoption of almost any means to bring about its reduction. Intensive study has shown that faulty methods of hiring and discharging men is the most important factor in labor turnover. Complete control over hiring and discharging by the foreman is a relic of outgrown industrial conditions; centralized hiring permits this work to be put on a scientific basis and also does away with many serious evils that cannot otherwise be reached. Centralized hiring does not impair the authority of the foreman; he hires his men from the employment office and discharges them back to it, instead of from and to the street. The employment manager, being a direct representative of the employer, tends to restore the former relation of direct intercourse between employee and employer that was helpful in avoiding friction between them. Being a specialist, he is able to bring special knowledge and skill to bear upon the task of selling employment in his concern to desirable workmen; lie is also able to give the foreign workman the special attention he requires. Employment managers have been used for the past few years by a number of large organizations, a few of which are engaged in the mining and metallurgical industries. They have invariably reduced labor turnover, in some cases to as little as one-tenth of what it had been. So great a reduction is due in part to other changes made in the light of the data made available by scientific study of the labor problem. In my former paper on personnel work1 I advocated the more general use of the employment manager in mining and metallurgical enterprises as a means of reducing labor turnover. The form of organization recommended seems not be to understood by all, and I have requested the privilege of explaining it at greater length, since it is perhaps the most important factor of all in personnel work, and has a vital influence on the cost sheet of every industrial enterprise.

Jan 2, 1918

By J. R. Eckel

It has long been known that mud properties affect drilling rate and that drilling with water is as much as six to .seven times faster than with mud. However, it is not known why drilling rates with mud are lower. Recent studies show what fluid properties govern microbit drilling rate and also provide a quantitative correlation of these fluid properties and hydraulics with microbit drilling rate. All the microbit tests reported in this paper were made with a low permeability (about 10 md) limestone. They were conducted at constant bit weight and rotary speed with varying fluid properties, flow rate Q and nozzle dinnteter d. The tests showed that (1) drilling rate in a given system with constant circulating rate and nozzle velocity is a function of the kinematic viscosity [viscosity /density, (cp)/ p (density)] of the drilling fluid measured at near bit nozzle shear rates; (2) the combined effect of fluid properties and hydraulics on microbit drilling rate is defined by a Reynolds number function (kQp/dp); (3) for the same kinematic viscosity, drilling rate is independent of solids content; and (4) for the same kinematic viscosity, drilling rate is independent of fluid loss. INTRODUCTION The fact that mudding up reduces rate of penetration is well known, but the reduction varies from well to well. The rate with mud may be 80 percent of the water rate or it may be as low as 15 percent. Since this reduction of up to seven-fold takes place under conditions of constant bit weight, rotary speed and mud circulating rate in a uniform formation, it can only be a result of the change in fluid properties. Previous work1-" both in field tests and in laboratory microbit tests) showed that drilling rate with mud is lower than with water (Figs. 1 and 2). Microbit tests also confirm, at least qualitatively, the field observation that drilling rate slows with increased pressure differential from borehole to formation (Fig. 3). The qualitative effect of drilling rate of bit weight, rotary speed and rate of mud circulation are also the same for the field and microbit rig. For these reasons, the industry generally accepts microbit results as being qualitatively meaningful in terms of field application.

By E. L. Estabrook, H. H. Hill

This report summarizes the information that was obtained by the Committee on Unit Operation in Eastern United States and in the foreign countries. Letters and questionnaires were sent to all of the Eastern members of the Petroleum Division of the American Institute of Mining and Metallurgical Engineers and to those who are living outside of the United States, asking them to advise the Committee of any unit operations that are in effect in the various countries of the world and to furnish the names of men to whom inquiries should be directed for detailed information on the different projects. The response to the Committee's request is worthy of note. Practically all of the members who had knowledge of foreign operations replied to the questionnaire and not only furnished information that was of value to the Committee, but they evidenced a real interest in the subject of unit operations and assured the Committee of their willingness to assist in every way possible in order to make the study a success. The Committee wishes, at this time, to express its appreciation of the excellent cooperation that was received from the members of the A. I. M. E. to whom questionnaires were sent. Unfortunately, the limited time that has been given to this survey did not permit the collection of detailed data on the different unit operations that are now in effect. It required several weeks to get back replies from the members located in some of the foreign countries and as a result the men who were asked to furnish information on the various projects have not had sufficient time to submit the detailed data that were requested. The Committee has been assured, however, that information relating to a number of unit operations will be furnished in the near future. Part of the delay has been due to the fact that the purpose of the study was not understood and because the terms "unit" and "near-unit" operations were not clearly defined. In the foreign countries, practically all of the operations in noncompetitive fields are on concessions or leases that have been granted to a single company and for that reason

Jan 1, 1930

By Edward Keller

ALTHOUGH the subject matter contained in this paper is presented under a new title, its writing was induced by the work of S. Skowronski and K. W. McComas.1 A discussion of the latter is here combined with the presentation of new and independent data. The physical constants quoted by the authors of that paper, such as melting and boiling points, as also the chemical reactions of the substances involved, are so well established that the numerous confirmatory experiments and their application to metallurgical conditions leave little or no room for criticisms. On the contrary, they will greatly aid to dispel any lingering skepticism as to possible considerable losses of copper accruing when the metal is melted in the presence of its own and, probably, other chlorides and when no provision is made for the recovery of volatile products. Exception may be taken, to some degree, to that part of the work under the caption Melting Drillings of Copper Mixed With Sodium Chloride. These experiments should have been extended in order to make the implied reactions clear and the results convincing. The latter are stated to be, "that when sodium chloride is present above certain minimum quantity relative to copper some of it is found to volatilize in the melt while another part reacts with the metallic copper to produce the volatile cuprous chloride, and that When smaller quantities of sodium chloride are present the reaction is complete and all chlorine is found to have volatilized as cuprous chloride." Metallic copper and sodium chloride are mentioned as the sole reagents in this chemical process, acting, according to the authors, in a neutral atmosphere of carbon dioxide. The chemist, quite naturally, will inquire into the formula according to which that reaction takes place and find that it would present itself as follows: 2Cu + 2NaC1 = 2Na + Cu2Cl2 It would appear that the truth of this formula will be challenged and a more rational explanation of the reaction sought. Apparently, carbon dioxide is neutral relative to metallic copper in its molten state; whether it remains neutral in the presence of sodium chloride is quite another question. Does it not at that high temperature become an oxidizer and do not the conditions of the reaction change to those expressed in the following formula? 2Cu + 2NaCl + 2002 = Na2CO3 + CO + Cu2Cl2

Jan 9, 1919

By Thomas M. Drown

IN the course of some experiments on the analysis of pig iron, I heated, in a platinum crucible, some borings of a graphitic pig iron with sodium carbonate. When the crucible was at a full red heat and the carbonate was thoroughly fused, I noticed a lively ebullition of the mass, and an escape of gas, which burned on the surface. On investigation this gas proved to be carbonic oxide, and on examining the borings in the bottom of the crucible after an hour or two, they were found to be perfectly malleable, although unchanged in general form and appearance. Analysis showed that the carbon was completely removed. I then repeated the experiment, to ascertain whether the silicon and phosphorus were affected, and found that these elements too were largely removed, and could be found in the fused mass as alkaline silicates and phosphates. In order to ascertain whether the removal of the silicon and phosphorus was merely a surface action or whether the reaction really extended into the mass of the iron, I tried the following experiments : A number of bars of pig iron were cast about one foot long and planed down-accurately to one inch section. These were immersed in a large wrought-iron pot full of molten sodium carbonate made by fusing the commercial bicarbonate of soda. Through the kindness of Mr. Frank Firmstone, Superintendent of the Glendon Iron Works, Easton, I was enabled to keep this pot at a reasonably constant high temperature for a long time in one of the hot-blast ovens. One of the bars was removed from the pot every twenty-four or forty-eight hours, according to the rapidity of the action, and after cooling was broken and the fracture examined. The change from pig iron to malleable iron was progressively inwards and always sharp and easily recognized, the rate of progression being in a decreasing ratio with the time. The temperature of the oven had evidently

Jan 1, 1879

By H. C. Chao, W. F. Hosford, L. H. Van Vlack

The negative "plastic Poisson's ratio" suggested in earlier studies of Mus deformation is analyzed, and the results are verified experimentally with NaCl crystals. In the early stages of deformation where the primary {110}(110) slip predominates, compression along. the [001] direction produces contraction along the lateral [011] direction plus a compensating expansion along. the [100] direction. With additional strain, the primary slip is supplemented by secondary {111}(110) slip so that the above contraction diminishes and a more typical deformation appears. THE shape change of bee and fee crystals deformed by compression or tension along [011] has been analyzed in some detail and shown to be responsible for the development of peculiar microstructures in [011] fiber textured polycrystals of these metals.1'3 This paper concerns the unusual shape change accompanying [011] compression of NaCl crystals. It is the direct outgrowth of an earlier investigation of the deformation of manganese sulfide inclusions in steel.3,4 In that investigation, cylindrical specimens of steel containing small oriented crystals of MnS were prepared by powder metallurgy and plastically compressed. The flow of the inclusions was determined relative to that of the steel by sectioning the composite and measuring the length-to-width ratio L/W of the inclusion and diameter-to-height D/H ratio of the steel cylinder on the plane of section. These L/W ratios, normalized by dividing by the initial LO/WO ratio of the inclusion, were compared with the normalized D/H ratio of the steel cylinder. Of particular interest here are the deformation characteristics of an inclusion oriented with [Oil] parallel to the compression axis. When measurements were made on sections parallel to the (100) plane of the inclusion, the L/IV ratios were only slightly in excess of unity, indicating a high apparent hardness of the [011] criented inclusion. However, measurements on a (011) plane of section resulted in L/W ratios which were much larger, Fig. 1. These observations prompted an analysis of the strains resulting from slip in an MnS crystal compressed along [011.]. CRYSTALLOGRAPHIC ANALYSIS Manganese sulfide has the NaCl crystal structure, and the predominant slip system is {110}(110). A secondary system, {111}(110), has also been reported.= {110}(110) Slip. When a crystal is subject to a uni-axial compressive stress 011 along [011], four slip systems, (101)[101.], (101)[101.], (110)[i10], and (110) [ 110], will be equally stressed with a shear stress t = 0.2 011 while the other two {110}( 110) systems will be unstressed. The normal strain En along any reference axis n resulting from slip is given by Schmid's law: en = S COS ?in COS in ?i 111 where ?in and +in are the angles between n and the i slip direction and n and the i slip plane normal, respectively, and where ?i is the shear strain on the i slip system, For the four active slip systems above, the cos ?in cos +in terms are all equal when the reference axes are the [011] compressive axis, [011] and [ 100]. Eq. [I.] therefore reduces to en - cos ?n cos +ny [2] where y =S?i for all slip systems. Substituting the appropriate angles, Eon = 0.25? 110 eon - 0.25y110 [3] €100 = -0.50y 110 The interesting feature of Eqs. [3] is that they predict that the strains in the [011] and [011] directions, resulting from {110}(110) slip, are equal and of the same sign. Thus when a crystal is compressed along [011], it will contract along the lateral [oil] direction

Jan 1, 1967

By Evan Just

Government aid, regulation, and participation in the mineral industry are not new; they date back to the time when man first adopted communal living. Even in primitive tribal life, the obtaining of arrowhead or ceramic materials, washing of gold, or mining of copper were specialized activities, under tribal sponsorship. Later, when kingdoms, dynasties, and hierarchies developed, titles to mining properties were held by the sovereign or the state, work usually being done by slaves. Title acquisition through denouncement developed in Europe in the late Middle Ages and spread to the Western Hemisphere with the Spanish and Portuguese empires. Denouncements still recognized the rights of the sovereign in the requirement to pay royalties, which practice continues in many places today. Thus, anyone who views government participation in mineral activity as "encroachment" has no historical perspective. Only in a few countries and for a few generations have private interests enjoyed the right to exploit mineral deposits without the specific consent of the sovereign or without payment of royalty. Governments and the mineral industry have been linked together by other factors. Governments have had special interest in metals and minerals as stores of value and for armaments. Spanish conquests in the New World were energized by the lure of gold and silver. Pursuit of gold led to the American seizure of California in the days of the Forty-niners. The strategic importance of minerals in our own times has called for special steps to stimulate production in national emergencies and to prevent the enemy from acquiring mineral supplies. Our export controls to deny certain minerals to unfriendly countries, purchases for Government stockpile, and subsidies for domestic production are examples. Production regulation by state governments of oil and gas has become a well established routine. In brief, the mineral industry has never lacked aid, regulation, and participation by governments. The entrepreneur who wishes to explore for or develop minerals must deal with governments in most areas before he can begin, because mineral rights are reserved by them. He can proceed through discovery and de-

Jan 1, 1964

By Carl H. Beal, E. D. Nolan

In February, 1918, the conclusion was published by Lewis and Beal "that wells of equal output on the average will produce equal amounts of oil in the future, regardless of the ages of the wells." This conclusion was based upon the study of data collected principally in Oklahoma and was not known at that time to be true for other oil fields. An abundance of statistical proof was later collected by the senior author of the present paper, which showed that the conclusion was undoubtedly well founded and that it applied to other fields as well. Accordingly, it was later restated2 as the "law of equal expectations" as follows: "If two wells under similar conditions produce equal amounts during any given year, the amounts they will produce thereafter, on the average, will be approximately equal, regardless of their relative ages." Although only scanty data from the California oil fields were available at the time this publication was prepared, sufficient information was analyzed upon which to base the insert on Fig. 80, which showed beyond a doubt that the law held at least for a part of the Midway oil field in California. Recently the authors have collected more complete data in California, and it is the purpose of this paper to explain the method used in demonstrating the truth of the law and, in addition, to give several methods by which curves constructed in accordance with this law can be used in a practical way with ease and accuracy. The Family Curve The law of equal expectations means that each individual of a group of wells producing under similar conditions will decline along approximately the same type of curve, the rapidity of decline varying with the output

Jan 1, 1921

By Alex Boozenny

The results of potential measurements between 1) a titaniurn electrode in NaCl-TiCl, melts and a graphite-cizlorine reference electrode and 2) a titanium electrode in NaC1-Nu "melts and a graphite-chlorine reference electrode show that the following relationship expresses the equilibrium relationship between the TiCl, and the dissolved metallic sodium concentrations, expressed in mole fraction units, in dilute NaCl welts at 850°C. The results of potential measurenments between a graphite electrode in NaCl-TiCl, melts that were saturated with TiCl, and a graphite-chlorine reference electrode, when combined with the standard free energy data given in literature, gave the following expression for the equilibrium relationship between the TiCl, and TiCl, concentrations, expressed in mole fraction units, in dilute NaCl melts at 850°C. These relationships are for melts in equilibrium with pure titanium. In impure systems, less sodiurn and more TiCI, can be copresent with a given concentration of TiCl,. AFTER 10 years of existence, the titanium metal industry still relies on the original Kroll and the sodium reduction processes for the only important means of converting titanium-bearing ores to titanium metal via production of titanium tetrachloride as an intermediate. Through years of modification and development these two processes have evolved to a point where any further major economic advances in the field of titanium metal production must be achieved through implementation of processes which are distinct departures from simple magnesium or sodium reduction of titanium tetrachloride. Concurrently with the refinement of the Kroll and sodium reduction processes, industries and government have sponsored research and development in the field of producing titanium by electrolysis of oxides,' carbides,' and halides3'4 in fused salt media. However, the incomplete understanding of the physical chemistry of fused salt systems has in many cases hindered the development of promising new titanium production processes to the point where they will have a clear advantage over the processes presently employed. Fortunately the volume of information on fused salt physical and electrochemistry is increasing at an accelerating pace. The first approaches tbward investigating the electrochemical behavior of fused salt systems have been the measurements of equilibrium potentials of metals immersed in melts containing their halides.' Some work on the kinetics of fused salt electrochemical processes has been reported.'09" Some descriptions of the structural composition of fused salt systems are also available. The work described herein is a continuation of the study of metal electrode potentials in fused salts. Specifically, this contribution to the growing store of fused salt chemistry information presents a description of the equilibrium relationships between the concentrations of titanium dichloride, titanium trichloride, and metallic sodium in fused sodium chloride. The investigation of the titanium dichloride-titanium trichloride equilibrium relationships is not completely new. Kellog and Krye and Melgren and opie15 have presented the results of chemical analysis of salts containing titanium chlorides. Flengas and lngrahaml' have published the results of an investigation of these equilibrium relationships obtained by measurement of electrode potentials in a fused NaCl-KC1 mixture. The investigation described herein differed from that of Flengas and Ingraham principally in the use of straight NaCl as the solvent in place of the more costly and more difficult to purify mixture. This investigation was conducted in three parts. First, the equilibrium potentials of titanium in sodium chloride containing known concentrations of titanium dichloride were measured. A graphite-chlorine electrode was employed as reference. Second, the equilibrium potentials of titanium immersed in sodium chloride containing known concentrations of elemental sodium were measured. Third, the equilibrium potentials of graphite immersed in titanium tetrachloride-saturated sodium chloride containing known concentrations of titanium trichloride were measured. The results of these three related investigations are presented in the above order. The results are combined with the thermodynamic properties of titanium chlorides and sodium chloride, obtained from literature, to give the titanium dichloride-titanium trichloride-elemental sodium equilibrium concentration relationships. In the test, whenever a melt contains titanium chlorides in predominantly divalent form, the melt

Jan 1, 1962

By Jean Howard

RECENT attempts to produce secondary recrystalli-zation in high-purity iron have given conflicting results. Coulomb and Lacombe1'2 did not find it but Dunn and Walter3,4 did. The latter workers have stated that (100) [001] and/or (110) [001] orientations develop depending on the oxygen content of the annealing atmosphere. This Technical Note records results which are in agreement with Dunn and Walter in so far as it shows that secondary recrystallization can be produced in high-purity iron, but does not confirm that both types of orientation are obtainable. Similar observations have been made on chromium-iron and molybdenum-iron, although when this technique is used on 3 1/4 pct Si-Fe, both types are obtained as in the work of Dunn and alter.' Pure iron strip was cold-rolled from sintered compacts prepared from Carbonyl Iron Powder-Grade MCP of the International Nickel Co. (Mond) Ltd. The powder contains about 0.5 pct 0, 0.01 pct C, 0.004 pct N, (0.002 pct S, $0.005 pct Mg and Si, and 0.4 pct Ni—that is, it is substantially free from metallic impurities other than nickel, which is thought to be unimportant in the present work. The iron powder was (a) pressed at 25 tons per sq in. into blocks measuring 3 by 1 by 0.3 in., (b) deoxidized in hydrogen (dewpoint -60°C) by heating first at 350°C and then at 600° C until the dewpoint returned to -60°C at each temperature and (c) sintered in hydrogen (dewpoint -40°C) at 1350°C for 24 hr. (when dewpoint is referred to in this Note, it is the value as measured on the exit side of the furnace). The sintered compacts were cold-rolled to 1/8 in., annealed in hydrogen (dewpoint -60°C) at 1050°C for 12 hr and cold-rolled to 0.004, 0.002, and 0.001 in. with inter-anneals at 900°C for 5 hr and a final reduction of 50 pct. Final annealing of strip between alumina or silica plates at 875" to 900°C in hydrogen with dewpoints of -20°, -55" and -80°C produced secondary grains with the (100) in the rolling plane; the extent of secondary recrystallization was greatest when the dewpoint was -55°C. Annealing in a vacuum of 2 x 10"5 mm Hg at the same temperature produced no secondary recrystallization at all. With strip thicker than 0.002 in. very few secondary crystals developed whatever the conditions of annealing. Using a processing schedule somewhat similar to that described above, secondary recrystallization was produced in two bcc alloys of iron, viz. 80 pct Fe + 20 pct Cr and 96 pct Fe + 4 pct Mo. The former was reduced to final thicknesses of 0.001 to 0.004 in. and the latter to final thicknesses of 0.001 to 0.016 in. With the chromium-iron, a final anneal at 1250°C (found to be the most effective temperature for developing secondary crystals in the 0.004-in material) with a dewpoint of -25°C produced a greater degree of secondary recrystallization than with dewpoints of -50°C or -20°C. Secondary crystals developed in strips of all thicknesses from 0.001 to 0.004 in. Final annealing in vacuum produced no secondary crystals at all. For the molybdenum-iron a temperature of 1200°C was most effective. It was found that a dewpoint of -50°C during the final anneal gave better results than a dewpoint of -25 "C on the 0.008 in. material. Final annealing in vacuum gave slightly worse results than annealing in hydrogen with a dew-point of -50°C. Secondary crystals were developed in strips of all thicknesses up to 0.008 in. The experiments show that the extent of secondary recrystallization is a maximum for certain critical values of oxygen content of furnace atmosphere and annealing temperature, and that these values are different for different alloys. The thinner the material, the less critical these values are. The general conclusions are that secondary recrystallization can be obtained in high-purity iron, chromium-iron, and molybdenum-iron, using a processing schedule similar to that which will cause the phenomenon to take place in high purity 3 1/4 pct Si-Fe. Unlike the silicon-iron, however, only the (100) (0011-- orientation has been produced in these alloys, irrespective of the temperature of final annealing and the oxygen content of the furnace atmosphere. The information used in this Note is published by permission of the Engineer-in-Chief of the British Post Office.

Jan 1, 1962