Search Documents

By Tayler H. Bingham

Personal consumption expenditures represent roughly two-thirds of total of GNP. While these expenditures directly account for only a small portion of total natural resource consumption, they account for a significant proportion indirectly. The reason is that all economic activity can be shown to be interrelated and that the intermediate production sectors, which are the primary users of natural resources, represent the interindustry transactions necessary to produce all final goods, including consumer goods. This paper provides a discussion of the methodology and quantitative estimates in physical units of the interrelationships between 15 major nonenergy resources and 6 energy resources and 477 personal consumption expenditure items.

Jan 1, 1977

By W. Arthur White

Underclay squeeze is the plastic flowing of underclay below coal pillars into mined-out entries and rooms. Squeezes may be caused either by wet mine conditions where the moisture is taken up by the clay-making it more plastic-or by the presence of certain clay minerals, such as mont-morillonite, which are plastic when there is enough natural moisture. Under either condition, sufficient stress will cause the underclay to flow. Squeezes may fill an entry or room within several hours, or it may be several months before movement stops. Squeeze areas commonly cover hundreds or thousands of square yards.

Oct 1, 1956

By L. G. Laureau

This paper is presented to call the attention of steel-manufacturers to the need of further reform in the manner of casting and handling ingots. The problem of making the work usually performed in and around the casting-pit less dangerous to the men and less costly to the management is one which has occupied the minds

Jan 1, 1885

By J. L. Hendrix, R. B. Dix

A study was made of the United States Bureau of Mines chlorine-oxygen leaching process for complex sulfide concentrates. The investigation sought to determine the kinetic order and mechanisms involved in the reactions between galena and sphalerite with chlorine. The influence of copper on the extraction rates was also studied. It has been shown that the rates of reaction of chlorine in aqueous solutions with sphalerite and galena are both zero order at 373 K with rate limiting step being the chemical reaction. Addition of cupric chloride increased the extractions of both lead and zinc.

Jan 1, 1981

By Öner Yücel, M. Zeki Dogan, A. Metin Ger

Technical and financial feasibility studies conducted at the Middle East Technical University, in Ankara, Turkey, have revealed that a 400 km long prospective slurry pipeline between Hasançelebi and Iskenderun could efficiently and economically transport iron concentrates, with a size of 55%-325 mesh and of amounts varying between 0.25 and 8.0 million tonslyear. Particularly for annual throughputs above 500,000 tons, favorable results have been obtained regarding the processing of the ore, the applicability, the transport cost, and the foreign ex- change currency savings.

Jan 1, 1980

The Institute is custodian of funds for support of numerous gold medals and prizes and has representatives on boards awarding still others. Details regarding the Institute Awards are given be- low. The Institute is represented on the boards of the John Fritz Medal, the Hoover Medal and the Washington Award, in connection with the three national societies of Civil, Mechanical and Electrical engineering; and, also, in the case of the Washington Award, with the Western Society of Engineers. The Institute is represented with these four societies on the committee in charge of the Alfred Noble Prize.

Jan 1, 1934

By I. Iwasaki, R. Titi-Manyaka

Chlorination and chloridization behaviors of pyrite, pyrrhotite, marcasite, chalcocite, covellite, galena, sphalerite, heazlewoodite, and elemental sulfur were investigated by thermogravimetric analysis. The possible reaction mechanisms are discussed on the basis of the theoretical weight changes and thermodynamic considerations. Chlorine is a more effective chloridizing agent than hydrogen chloride. In the light of the experimental results, a scheme for producing nonferrous metal chlorides, molten sulfur, and ferric oxide from complex sulfide flotation concentrates is discussed.

Jan 1, 1974

JoHN W. BELL, Montreal, Quebec, Canada (communication to the Secretary*).-Mr. Taggart's reply illuminates a puzzling element in his original paper. Unconsciously, he has allowed practical considerations to influence some of his conclusions. In certain cases, he accepts the direct conclusions indicated by his Stadler efficiencies, and these are proved wrong by both the Rittinger and practical method for estimating efficiency. In other cases, a direct conclusion based on his Stadler figures would be so unsatisfactory to him, that he is. compelled to argue how he could have obtained satisfactory results if lie had crone something that

Jan 10, 1917

By Robert H. Weber

Increasing acceptance of perlite products, chiefly in the fields of lightweight structural aggregates and thermal and acoustic insulation, has led to expanding market demands that have encouraged many new producers to enter the field. In some instances, however, the failure of these producers to anticipate the variable response of perlite to conventional processing methods has led to difficulty in establishing an economical flowsheet by which a predictable specification product could be obtained. It is not the writer's intent to provide a solution to these problems, but rather to summarize their nature. It is to be hoped that members of the industry who have hurdled some of these obstacles will document solutions arising from their experience.

Jan 2, 1955

By Shosei Serata

Serious floor heave of up to 2.4 m in a 2.4-m high mine entry was eliminated by applying the stress control method of mining, as a last resort, at the No. 5 coal mine of Jim Walter Resources, Inc., in the Black Warrior coal basin near Birmingham, Alabama. Underground observation of the first 3-room entry created using the stress control method is discussed here. The behavior of the test entry, which eliminated the heave problem, is analyzed in relation to similar studies conducted in a salt mine under similar ground conditions by utilizing finite element analysis.

Jan 1, 1984

By R. E. Zimmerman, Shiou-Chuan Sun

An evaluation of the mechanism surrounding the froth flotation of coarse coal and mineral particles as a result of experiments conducted at The Pennsylvania State College. Maximum size ranges for both bituminous and anthracite coals were established as well as the factors affecting the floating of coarse particles.

Jan 5, 1950

By J. Winter, W. C. Setzer, A. J. Goldman

ANISOTROPY in cold worked tempers of commercial aluminum alloys is manifested in deep drawn products as protuberances or ears 45 deg to the rolling direction. This reflects the {123}(412) rolling texture.' In fully annealed material, 0 to 90 deg ears in and per-

Jan 1, 1970

By F. S. McNicholas

UNTIL the fundamentals of the physical behavior of rocks are completely understood, progress in block caving must proceed upon a cut and try basis. Criteria of rock failure are many and varied. If a rock mass behaved as a homogeneous isotropic solid, the problem would be greatly simplified. In practice we are never dealing with isotropic or homogeneous rock but with one that has been acted upon by geologic processes and which has pre-existing planes of failure. Under these complex conditions we do not find agreement. Actually there is little agreement between elasticians and physicists as to manner of failure in an isotropic homogeneous solid, although much progress has been made in the study of rock failure in recent years.

Jan 11, 1950

By S. N. Sharma, William Davis

Because of diminishing energy resources and rising energy costs, every industry is forced to carefully examine its pattern of energy consumption. The copper industry is no exception; current smelting practice begs for technological innovations that would improve the efficiency of its energy utilization. The thermochemical simplicity of copper metal production, as shown in Fig. 1, is deceptive. Designed from the same basic principles, there are four major commercial processes either in use or under construction; and others, such as the Mitsubishi process, are being developed.

Jan 5, 1977

By J. J. McKetta, O. L. Culberson

A preliminary investigation was made to determine the time required to attain equilibrium within the equilibrium cell for this system. Experimental and smoothed data are presented for the solubility of ethane in water for temperatures of 100°, 160°, 220°, 280" and 340 °F at pressures to 10.000 psia. The minimum solubility phenomenon disappears at 10,000 psia within this temperature range. INTRODUCTION .is a continuation of the investigation of the behavior of hydrocarbon-water systems, the experimental data on the solubility of ethane in water have been extended to 10,000 psia. The experimental apparatus, technique, materials, and analytical methods are essentially the same as previously reported.' TIME-CONCENTRATION STUDY Prior to the initial determinations of solubility in the ethane-water system. it was desired to establish the time

Jan 1, 1950

By R. H. Foley

It is difficult to consider any seam as unsuitable for longwall mining operation for something like 95% of British coal is produced by this system. The following is a brief report on how they do it-their techniques and equipment. Depth of working in British mines varies from about 150 ft to more than 3000 ft, with the average being about 1300 ft. Average seam thickness is approximately 40 in., but working seams vary from 16 in. to as much as 14 ft.

Jan 8, 1965

By Alfred E. Hunt

Professor EGGERTZ first published a method based upon the fact that, when steel is dissolved in dilute nitric acid, and heated until the separated flocculent carbonaceous matter goes into the solution, the liquid assomed a brown color proportionate in intensity to the amount of the combined carbon in the steel. This method has been so variously modified that at present but few chemists use exactly the same procedure. It is the object of this paper to present

Jan 1, 1884

By J. Van Oirbeek

The ash-fusion gas producer, blown with air preheated to a high temperature, was perfected by the Société des Houilléres de Saint-Etienne during the years 1920 to 1925, for the treatment of a mixture of ashy fuel and limestone. The temperature, about 1800° C., obtained by using hot air in running the producer, ensures the fusion of all the slag and the transformation into carbon monoxide of every particle of carbon contained in the materials treated.

Jan 1, 1937

Executive SIDNEY J. JENNINGS, Chairman GEORGE D. BARRON J. E. JOHNSON, JR. EDWIN LUDLOW ROBERT-M. RAYMOND Membership LEWIS W. FRANCIS KARL EILERS, Chairman J. E. JOHNSON, JR. LOUIS D. HUNTOON ARTHUR L. WALKER Finance GEORGE D. BARRON, Chairman CHARLES F. RAND BENJAMIN B. THAYER Library E. GYBBON SPILSBURY.1 Chairman. ALEX C. HUMPHREYS3 GEORGE C. STONE2 J. H. JANEWAY4 BRADLEY STOUGHTON Papers and Publications BRADLEY STOUGHTON, Chairman

Jan 2, 1919

By Y. J. Wang

A graphical technique by which the operating points for a two-fan ventilation system can be represented as the intersection of the modified fan curves is described. In constructing the diagram, the air quantities associated with the fans are considered to be independent variables and used as the axes of a rectangular coordinate system. The diagram may include, in addition to the modified fan curves, contour lines for resistances, pressures, and air powers. Procedures for drawing the diagram are discussed and illustrated with an example of the ventilation system.

Jan 1, 1986