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For the year ending February, 1926 PRESIDENT J V W REYNDERS, District 0 NEW YORK, N Y PAST PRESIDENTS E P MATHEWSON, District 0 NEW YORK, N Y WILLIAM KELLY, District 5 IRON MOUNTAIN, MICH FIRST VICE-PRESIDENT E DEGOLYER, NEW YORK, N Y TREASURER , CHARLES F RAND, NEW YORK, N Y SECRETARY FREDERICK F SHARPLESS, NEW YORK, N Y

Jan 1, 1923

By R. A. Deju, R. B. Bhappu

The theory of electrophoresis is briefly outlined and an apparatus which may be used for electrophoretic studies is explained. The results obtained using this apparatus are in agreement with those obtained by other investigators. How to solve some of the complications which occur in the measurement of zero charge and zeta potential is explained. It is believed that the apparatus described in this paper will allow rapid measurements of zeta potential, zero point of charge, electrophoretic mobility and zeta coefficient. For many years the phenomenon of electrophoresis has been studied, and much work has been done in designing an apparatus for better measurements of mobility, zeta potential and zero charge of minerals. Up to the present, most electrophoresis experiments have involved cumbersome equipment and tedious microscopic observation. The modified cell proposed in this paper obviates these drawbacks by using a Rayoscope together with a special system of lenses and filters. It therefore allows a faster and more accurate measurement of zero charge and particle velocity. THEORY Most authors currently regard zeta potential as the potential difference in an otherwise uniform medium between a point some large distance from the surface of the mineral and a point on the plane of shear. Fuerstenau,1 Miaw,2 and Gaudin and sun3 have performed some calculations of zeta potential using Henry's equation.4 Their results show wide discrepancies, probably due to differences in the past histories of the minerals used. The authors have also noticed this difference on determining the zero point of charge of quartz as shown on Table I.

Jan 1, 1967

By H. A. Schwartz

By analyzing cementite separated electrolytically from white cast iron of known composition and history, the distribution of silicon between austenite and cementite during and after freezing has been followed. The results constitute a contribution to our knowledge of equilibria in the ternary (metastable) system iron-carbon-silicon. Incidental information was obtained, also, with respect to the distribution of manganese, silicon, and phosphorus, when only relatively small amounts of each are present. The major conclusion of the paper is that during solidification, equilibrium is attained when the silicon is all rejected to the liquid phase, permitting silicon-free austenite to separate. OF THE outstanding investigators of the system iron-carbon-silicon, Gontermann,1 Charpy and Cornu-Thenard,2 and Honda,3 only the first touched on the chemical composition of the solid and liquid phases in equilibrium with one another. He concluded that his data did not permit a decision as to which of an indefinitely large number of pairs of compositions of liquid and solid would be found in any given case. If through the three dimensional equilibrium diagram of the iron-carbon-silicon system an isothermal plane is passed in the region of partial solidification, two lines of intersection with the liquidus and solidus, respectively, are obtained, also a point marking the alloys' composition. If, in this, plane, a straight line is drawn through the point, and intersecting both the liquidus and solidus isothermals, the two intersections mark a liquid and a solid alloy that may be chemically in equilibrium at the chosen temperature. From thermal data alone, Gontermann could not assign any particular direction to the line and, hence, could not determine which pair of conjugate points to choose.

Jan 7, 1924

By Michael Shaughnessy, O&apos

The outstanding features of the Coloinbian situation for the year 1929 were legal and political. The passage of Law 84 and the promulgation of the Regulatory Decree 150 were recounted in the review for 1928, as was also the Presidential proclamation suspending this law and its accompanying decree until decision could be reached in the suits filed against them before the Supreme Court and the Council of State. Early this year the Minister of Industries, Jose Antonio Montalvo, announced the appointment of a commission of foreign experts to aid in drafting a new petroleum law. He requested all of the foreign experts employed not to consult with the oil company representatives in Bogota, and these experts were therefore shut off from receiving any suggestions from those who had actually operated in the country and knew the conditions under which operations would take place. It was to be expected that the provisions of a law suggested under such circumstances would not meet operating conditions satisfactorily. The specific objections are stated in O'Shaughnessy's South American Oil Reports (April, 1929). An especially qualified commentator observes that one of the curious provisions of the proposed law was the high royalty on gas—5c. per 1000 cu. ft. of gas produced. There was also a provision requiring 20 per cent. of the stock of the company operating in Colombia to be offered for sale to Colombians. The bill failed to pass Congress in the closing hours of the session. The Supreme Court, in the meantime, handed down its decision on Law 84 of the previous year and Regulation 150 covering the enforcement of that law. Contrary to expectation, the majority opinion of the Court practically affirmed the constitutionality of both the law and the regulatory decree, with the exception of Article 20 and parts of Article 21 of the decree which referred specifically to the registration of private properties. At the time the suit was filed against Law 84 and Decree 150 the operation of these measures was suspended by the Executive. Law 84 and its Regulatory Decree 150 still remain suspended as the Council of State has not yet brought in a decision upon the questions raised in the suits instituted by the various companies against the law and decree, and at the moment of this writing it appears unlikely that such a decision will be reached by that body.

Jan 1, 1930

By A. M. Radigan, W. G. Prast

Various industrial minerals that are traded internationally receive support from governments, enabling these materials to be more competitive. The role of government in encouraging nonmetallics exports ranges from the ownership of an integrated mining company to partial or selective government ownership, to the sponsorship of exporter organizations. In certain cases, regional governments have a direct stake in the industrial minerals industry. This paper assesses the commercial impact of these involvements.

Jan 1, 1984

The age of specialization has made man increasingly dependent on a larger number of different metals and minerals. Overexploitation during World War II and lavish squandering of irreplaceable mineral wealth in the past has resulted in the rapidly approaching exhaustion of some of the major domestic ore sources. History clearly points out that the United States cannot continue to be a world power on an "import to survive" policy. A constructive program of development and appraisal of the nation's mineral wealth, including the planned conservation of her resources, must be adopted. Strictly speaking, conservation of minerals must mean the orderly exploitation of our resources and the prevention of waste in use, with due regard for the future. Real concern for the future may not extend beyond a few generations. Eventually science and invention should take care of the problems arising from shortages of some minerals, and the national defense aspects of domestic deficiencies can be provided for by stock piling and other measures. Early conservationists had this viewpoint; but with a rapidly developing industry and population, a farsighted policy that would deny full realization of immediate ambitions became unpopular. Consequently, the politically minded conservationist broadened the concept to include "prudent use of resources" and brought under the conservation umbrella

Jan 1, 1950

FRank FirmstoNe, Easton, Pa.: The effect of lead on brass seems to have been recognized by Berthier, and the facts published by him as early as 1818 (Ann. des Mines, 1st ser., iii., 1818, p. 347 et seq.). He there says expressly that copper containing lead makes " dry " (see) brass, and that, for the same reason, blast-furnace

Jan 1, 1898

By Frank E. Caropreso, William P. Badger

A hydrogen peroxide precipitate process has been adopted by Atlas Minerals for the recovery of uranium oxides from sodium chloride strip solutions. Adoption of the process was based on laboratory and plant tests comparing hydrogen peroxide with other precipitants. Plant operation has demonstrated that the hydrogen peroxide process consistently yields uranium concentrates of high purity and barrens of low uranium content. Increased U3O8 concentration in the product, reduced levels of impurities which incur penalties, and higher product density have produced economic advantages.

Jan 1, 1974

By M. T. Abasov

The work suggests an approach to the problem of optimally planning the drilling and development of gas fields. The approach is based on systems analysis and allows a joint optimal choice of the total number of wells in the field, their spacing in the reservoir, the diameter of production tubing, drilling dynamics, the number and spacing of drilling platforms and well pattern schemes for each plat- form as well. The optimal solution satisfies the set of technical- economical requirements and provides a minimum value of discounted total expenditures (capital costs plus operating costs). A mathematical model of the problem is presented. This work represents an extension of the authors&apos; previous investigations that formulated and solved problems of optimal drilling of oil and gas deposits by directional wells [1] and problems of optimal control of the number of active wells in multi-reservoir oil and gas fields [2], [3]. For construction of the mathematical model we choose a range (Nmin, Nmax) of possible values of the total number of wells, N, which should be drilled in the deposit. Here Nmin, Nmax are minimum and maximum numbers of wells correspondingly, that should be drilled into the reservoir. N[€](Nmin = N1, ... N[o], ..., Nm = Nmax). For simplicity a one-reservoir gas field is considered. It is assumed that: (a) wells are spaced in the reservoir uniformly, (b) there is a certain algorithm providing a uniform spacing of the given number N[o] ([0]=l, . . . , m) of wells in the reservoir, (c) the diameters of the production tubing for all the wells are the same. The relation Qz (x), i.e. the dependence of the cumulative output of gas from the cumulative "well-years" of operations is constructed for each diameter dZ from the given range of diameters d1< ...< dr.

Jan 1, 1977

By N. A. Ziegler

A CERTAIN amount of interest has been indicated recently in the resistance to oxidation at high temperatures of iron-aluminum alloys (rich in iron). Hautman1 published a paper in which some interesting results are given. According to his paper, only alloys containing at least 8 per cent aluminum indicate a marked improvement in their resistance to oxidation. At about this aluminum content, however, alloys become brittle, which considerably reduces their commercial value. About two years ago the author performed a series of experiments, the results of which are presented here. A series of iron-aluminum-carbon alloys was prepared by melting electrolytic iron, aluminum and high-carbon iron alloy in an induction vacuum furnace.2 The list of these alloys is given in Table 1. Each alloy was forged in the ordinary way to

Jan 1, 1932

By A. L. Labbe

SOON after the Cottrell treater was placed in operation in the Murray plant in 1918 to treat combined lead sinter and Wedge roaster smoke, it was noticed that the power flowing through the treater did not remain constant. This was indicated by the varying milliamperes and also by the total amount of power consumed by the rectifiers. At times, for then unknown reasons, the treater current fluctuated through a wide range of from 40 to 300 milliamperes. Fortunately, these variations in power did not affect the treater&apos;s overall recovery, as this installation consisted of three independent units in series, a feature which made the Murray Cottrell an outstanding installation over many years of operation. Water conditioning of the smoke as a means of improving recovery was already known, but was not adaptable to this installation for reasons of excessive corrosion, which had been the case with other treaters using water as a conditioner exclusively. Tests conducted on the smoke had proved conclusively that water vapor played no part in the fluctuation of power, and the same was true of the SO2 contents and dust burden of the smoke. Neither did temperature variations of from 150 to 400°F have any effect on the power. Finally it was noticed that the variation in power taken by the treater, and the efficiency of recovery, had some definite relation to the number of Wedge roasters operating, and particularly to the sulphur contents of the charge. This observation soon led to the discovery that free sulphuric acid was the conditioner for Murray smoke and that variations in acid contents of smoke accounted for fluctuations of treater power. Analysis of recovered dust revealed that only a few hundredths of a per cent free acid was necessary to maintain a very efficient recovery. Once this knowledge was available, the roaster charge was adjusted as to sulphur contents to produce the necessary acid conditioner. For a number of years this practice was followed, but with improvements in the field of flotation, excess pyrites were eliminated from the smelting picture, so with a change in metallurgical practice we were confronted with the problem of providing the deficiency in acid by some other means. The situation was aggravated and our problem of acid conditioning made more difficult by the increase in the lead contents of concentrates roasted resulting from better flotation methods. The first step towards introducing acid vapors into the smoke stream by accessory means was accomplished by boiling sulphuric acid in cast iron pots placed in an open fire box. Acid fumes evaporated from the pots together with the combustion gases from the fire box were discharged into the flue through a cast iron pipe. Capacity of the iron pots was quite limited because of the comparatively slow rate of evaporation and the use of lump coal as a fuel, which did not lend itself to practical temperature control. This method of firing resulted in frequent pot failures due to overheating. In spite of these incidental difficulties, encountered in any new venture, the pot evaporator demonstrated the practicability of fuming sufficient acid to make up the deficiency in that naturally evolved in the Wedge furnace operation. As time progressed, less and less high sulphur material was available for Wedge roasting, and the necessity for accessory acid conditioning reached a climax when the supply of this material was entirely eliminated. Since the cast iron pots could only evaporate a few hundred pounds of acid per day, and were costly to replace, the logical thought presented itself of spraying the acid in a heated chamber. This new type of acid evaporator was simpler and more economical to operate and had sufficient capacity to fume several thousand pounds per day. The attached fig. 1 presents the outstanding features of the new furnace. A is the vaporizing drum, which is heated by the combustion gases of coal stoker fire box, B. Acid is sprayed into the hot gas stream within the drum through a number of air-acid atomizers, C, and the acid vapor, together with combustion gases, is introduced into the smoke stream through two cast iron pipes extending to different points in the flue. The operation of this type of furnace requires control of temperature inside the drum to prevent overheating, which dissociates the acid vapor to SO, and eventually to SO2, with resulting loss of acid. The dissociation to SO, at elevated temperatures is comparatively high, and in some cases accounts for as much as 60 pct of the acid sprayed into the drum. To reduce the loss of acid, through dissociation, some Cottrell plants, where the rate of acid sprayed reaches at times 9 ppm, use two evaporating units. Fuming the acid into the smoke stream is only

Jan 1, 1951

We are glad to print the following letter from Herbert C. Hoover, who has recently been appointed Food Administrator, by President Wilson. Mr. Hoover has a tremendous task before him, and we are sure that mining engineers will give him their hearty support by responding to his appeal to stop the waste of food.

Jan 7, 1917

By Jack A. Kanz, Samuel R. Shortes, E. C. Wurst

Zinc diffusion into GaAs from the vapor phase through reactively sputtered SiO, films Izas been inrestigated for various zinc pressures at 1000"C. Diffusions were carried out in evacuated quartz ampules with elemental zinc and with various Zn-Ga alloys. Sputtered films have proved effective in lowering surface concentrations and preventing surface deterioration during diffusion. Approxin.ate complenzentary error-function impurity distributions were found when surface concentrations were reduced to approximately 3 -—4 x 10" atoms cm&apos;3 or less with dilute zinc sources or by diffusion through SiO, films. Zinc difhsions in GaAs tlzrough SiO, films produced more planar diffusion fronts than were observed with uncoated zuafers under identical conditions. A) Surface Deterioration During Diffusion. Device technolorn-- in compound semiconductors has been hampered by several difficult problems not normally encountered with silicon and germanium. 111-V and 11-VI compound semiconductors generally have volatile constituents at temperatures used for diffusion. To achieve specific junction depths in reasonable lengths of time, or to obtain particular impurity distributions and doping levels, it is often necessary to use temperatures which cause surface deterioration and erosion of the wafer. The resultant surfaces are generally unsuitable for devices. The type and extent of surface damage depends to varying degrees on the particular environment of diffusion and on the particular impurity in question. The most common type of deterioration results from simple dissociation of the gallium and the arsenic during diffusin.&apos; The deterioration process is significantly enhanced by thermal gradients in the diffusion zone, usually resulting in vapor transport and condensation at the cooler portion of the system. The resulting damage sometimes appears as a general haziness over the surface or an array of pyramidal etch pits characteristic of the particular orientation. Occasionally, erosion of the surface occurs uniformly over the wafer so that surface loss is not readily apparent. Workers in GaAs usually resort to the sealed-ampule type of diffusion system3"5 rather than the more conventional open system used for silicon and germanium. Another type of deterioration results from direct interaction of the impurity with the surface. The form of deterioration may vary from surface alloying, as in the case of zinc, to direct chemical attack and vapor transport of the reaction products, as in the case of sulfur. Surface alloying with zinc occurs at higher temperatures and source vapor pressures.4 The process is largely controlled by the amount of free gallium on the surface of the wafer in equilibrium with the arsenic lost to the system. The group-VI elements, sulfur, selenium, and tellurium, are commonly used donor impurities for gallium arsenide. These elements are characterized by high vapor pressures and high chemical

Jan 1, 1964

Jan 1, 1923

Jan 1, 1923

By M. G. Nicholas

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

Jan 1, 1963

By James H. Hance

Discussion of the paper of JAMES H. HANCE, presented at the New York meeting, .February, 1916, and printed in Bulletin No. 110, February, 1916, pp. 299 to 326. FREDERIC P. DEWEY, Washington, D. C. (communication to the Secretary*).-I wish to congratulate Professor Hance and to thank him for his extremely valuable addition to the fund of data upon this subject. It presents clearly conclusive and incontrovertible proof of the unreliability of drill samples of this class of metal for determining the value of such bullion. I am afraid, however, that his hope that some one in the mint service might continue such an investigation upon a more elaborate and exhaustive scale is, for the present at least, doomed to disappointment. As a practical matter, the mint service is not now particularly interested in segregation in crude bullion. So much trouble and friction arose, -both in the original purchase and in the transfer from one institution to another, in handling segregated bullion, that it became necessary to adopt drastic measures and now it is seldom attempted to determine the value of such bullion in the service. When bullion known or even suspected of being segregated is presented for purchase, it is at once strongly refined in the pot and the disturbing elements so far removed that concordant assays may certainly be obtained from the dip samples and a reasonably fair agreement obtained from drill samples. The mint service prefers that the owner should refine his bullion himself, but if he does not we will do it at his expense and return the slag to him when desired. Much work has been done in the mint service trying to arrive at the value of deposits of segregated bullion without strong refining. It was no unusual thing for such deposits to be melted three times at the purchasing office and to have 30 to 40 assays on the metal made before buying it. Yet when shipped to a mint it was found necessary to melt two or three times more and to make 15 to 25 assays before the mint would accept the bar, and there were considerable differences between the valuations of the two offices. In what was undoubtedly the worst case ever investigated, the purchasing office melted the deposit, 953 oz., three times, with a loss of 105.5 oz., and made 46 assays; the mint melted three times, with a loss of 6.6 oz., and made 28 assays. The mint allowed the purchasing office 1.178 oz. of fine gold more than the purchasing office claimed, while an extensive investigation of the mint samples by the Bureau, in which over 100 independent assays were made in various service laboratories, indicated that the metal carried 0.7 to 0.9 oz. more of fine gold than the mint allowed. Preliminary assays on the original metal

Jan 5, 1916

By Robert B. Fulton

Staurolite, an iron aluminum silicate mineral, is used industrially as a high value-in-use sand-blasting agent, as a premium grade foundry sand, and as the source of aluminum in portland cement manufacture in areas where the aluminum constituent is not economically available from shale or argillaceous limestone. It is produced by E. I. du Pont de Nemours & Co. as a coproduct in titanium mineral production in Florida where it was first recovered on a commercial scale in June 1952 from the Pleistocene sand deposit known as Trail Ridge. In the Trail Ridge deposit it comprises about one-fifth of the heavy minerals, the principal other heavy mineral constituents being ilmenite, leucoxene, rutile, zircon, kyanite, sillimanite, and tourmaline. Staurolite and the other silicate nonconductive heavy minerals are separated from the conductive titanium minerals on high-tension separators. The silicates are then separated from one another magnetically, the staurolite being relatively magnetic. In the total processing, 200 tons of raw sand yield 7 tons of heavy mineral concentrate from which about one ton of staurolite is recovered. This process yields staurolite concentrates of the characteristics given in Table 1. These concentrates are sold as three products with the size distribution of subrounded particles shown in Table 2. All three grades are used in sand-blasting for cleaning metal, for paint removal, and for cleaning buildings. Staurolite compares favorably with lower unit cost abrasives, such as boiler slags and mineral aggregates, in applications where the abrasive is used only one time and is not recovered. Because it is hard, fine, clean, and dense it can reduce blasting time, with less material reportedly being required [ ]

Jan 1, 1983

By E. J. Schmitz

This trip, beginning at Springfield, August 12, 1897, and ending at the same place fourteen days later, extended south and southeast through Christian, Ozark and Taney counties,

Jan 1, 1899

For the year ending February, 1919 PRESIDENT SIDNEY J. JENNINGS NEW YORK, N. Y. PAST PRESIDENTS L. D. RICKETTS NEW YORK, N. Y. PHILIP N. MOORE ST Louis, Mo. FIRST VICE-PRESIDENT C. W. GOODALE BUTTE, MONT. TREASURER GEORGE C. STONE, NEW YORK, N. Y. SECRETARY EMERITUS ROSSITER W. RAYMOND, NEW YORK, N. Y. SECRETARY BRADLEY STOUGHTON NEW YORK, N. Y.

Jan 7, 1918