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By George B. Waterhouse

Jan 1, 1933

By T. A. Read, H. M. Otte

THEORETICAL analysis by Wechsler, Lieberman and Read of the crystallography of martensite formation has shown that the requirement for the existence of a macroscopically undistorted plane between austenite and martensite permits a calculation of the indices of the habit plane of the marten-

Jan 1, 1958

Jan 1, 1898

By H. M. Strong, R. A. Oriani

THE technological interest attaching to light, age-hardening alloys for structural uses has been pointed out to one of us.1 A potentially interesting alloy would be titanium-rich Ti-Mg alloy, provided that sufficient solid solubility exists. or could be induced at high pressure. and provided also that age hardening can be induced by proper temperature and/or pressure annealing. It was decided therefore to explore the feasibility of producing a Ti-Mg alloy in the high-pressure apparatus. Experimental. Three high-pressure runs have been carried out. In each case the geometry of the sample was that of a cylinder of titanium of commercial purity, into which a narrow hole had been drilled along the axis; this hole was filled with magnesium wire,

Jan 1, 1967

By Akira Yazawa, Alžbeta Gubcova

RECENT lead-smelting techniques have tended toward use of high-grade concentrates with minimum amounts of flu, accompanied by profitable employment of roast reaction.1-5 In order to better understand these smelting processes, thermodynamical calculations have been carried out on the Pb-S-0 system, and the results obtained have been presented in isothermal reaction diagrams in which log Ps, and logPo, were the axes. The diagram thus constructed seems to be more convenient to grasp the equilibrium aspect than those published hitherto.6-8

Jan 1, 1968

By E. V. Manlapig, David J. Spottiswood

In recent years great advances in the automatic control of flotation plants have been made, mainly due to the development of reliable sensing instruments to monitor process performance and the development of an adequate understanding of system responses to process disturbances. Some of the control strategies used in flotation plants which apply computer control are presented here. These schemes, which involve the control of collector; depressant, frother, and air and pulp level, are analyzed with respect to their control objectives, control variables, and the instrumentation involved. The knowledge gained in understanding these strategies may be applied in the dew and implementation of control system in other concentrators.

Jan 1, 1981

Seattle offered sunny, dry weather to about 2500 mining men who assembled September 10 to 14 for the 1961 American Mining Congress. The impact of snappy sessions on national mineral policy, state of the industry and foreign competition (to name only a few) was somewhat overshadowed by enthusiasm of conventioners for salmon fishing. This lordly fish, which mysteriously runs to its hatching place to spawn and die at this time of year, was not cooperating with the anglers in Puget Sound. However, this did not prevent consuming ample amounts of the deliciously prepared Quinault salmon at the "Potlatch" celebration.

Jan 10, 1961

By Dorsey Hager

One of the most interesting fields in North America was discovered, early in 1922, near the towns of Sunburst and Kevin, Toole County, Mont. This field produces oil from the Jurassic beds, which heretofore have been of but little importance as oil producers, and promses to be the

Jan 1, 1923

By C. Y. Chen

Public Law 95-87, the Surface Mining Control and Reclamation Act of 1977 (SMCRA), Section 516 (b), requires the underground coal mining operator to "adopt measures consistent with known technology in order to prevent subsidence cawing material damage to the extent technologically and economically feasible, maximize mine stability, and maintain the value and reasonably foreseeable we of such surface lands, except in those instances where the mining technology wed requires planned subsidence in a predictable and controlled manner.. . ." Congress also directed the Secretary of the Interior to promulgate regulations to implement the law. As a result, the control of subsidence from underground coal mining to minimize surface damage has become the mandate of a federal law. This paper discusses the mechanics of subsidence and the effects of subsidence on ground features. This paper also summarizes some measures used to minimize the possibility of damage to structures as a result of subsidence due to underground coal mining.

Jan 1, 1984

By C. R. Pelley

This paper describes the analytical characteristics of Western subbituminous coal and the manner in which these characteristics apply to their use in a utility-sized steam generator. It compares these characteristics with those of typical Midwestern coal and Eastern bituminous coal. The paper also reviews in detail the design considerations that must receive attention when various blends of these three coals, or any combinations thereof, are planned to be used. This research paper describes variations in analytical and utilization characteristics when coals from different origins are blended in order to achieve a predetermined sulfur content for the purpose of predicting sulfur oxides emissions as they affect environmental regulations and the resulting alterations in utilization characteristics such blending would cause, and how such blends of coal would affect a utility-sized steam generator.

Jan 1, 1979

By Thomas E. Howard

Recipient of the 1975 D. C. Jackling Award - "For his vision and initiative in defining, planning, directing, and accomplishing mining research programs; for his leadership in focusing worldwide attention on the need for research to improve underground excavation for mining and civil applications; and for his lecture. . ."

Jan 1, 1976

By E. C. Weichel, J. H. Carpenter, J. C. Detweiler, J. L. Gillson, J. P. Wood

ILMENITE, rutile, zircon, and other heavy minerals are found in small amounts in the sand that covers most of Florida. Small enriched deposits occur on the beaches and coastal dunes. One beach deposit east of Jacksonville was worked during World War I and another near Vero Beach during World War 11. Both ceased operation when the resumption of imports reduced prices.

Jan 8, 1953

By Dorsey Hager

One of the most interesting fields in North America was discovered, early in 1922, near the towns of Sunburst and Kevin, Toole County, Mont. This field produces oil from the Jurassic beds, which heretofore have been of but little importance as oil producers, and promses to be the

Jan 1, 1923

By C. R. Pelley

Abstract-This paper describes the analytical characteristics of Western subbituminous coal and the manner in which these characteristics apply to their use in a utility-sized steam generator. It compares these characteristics with those of typical Midwestern coal and Eastern bituminous coal. The paper also reviews in detail the design considerations that must receive attention when various blends of these three coals, or any combinations thereof, are planned to be used. This research paper describes variations in analytical and utilization characteristics when coals from different origins are blended in order to achieve a predetermined sulfur content for the purpose of predicting sulfur oxides emissions as they affect environmental regulations and the resulting alterations in utilization characteristics such blending would cause, and how such blends of coal would affect a utility-sized steam generator.

Jan 1, 1978

By Ichiro Ito

At present, in Japan, the application of in-place leaching technique to the mined-out stopes has been carried out at two copper mines in a comparatively large scale. These mines are the Kosaka mine and the Tsuchihata mine, both are situated in the north-east district of Japan. At first, the author would like to tell about the in-place leaching operations and their results at these two mines. Then, the problems involved in the application of in-place leaching technique to the Japanese metal mines and the possibility of the future development of this technique in Japan are referred, too. Next, as to the research works, the author would like to explain briefly about some of the important results obtained in the recent studies on in-place leaching as well as on bacterial leaching in Japan.

Jan 1, 1976

By Sir Nathaniel Barnaby

We must not conceal from ourselves that, against the perils arising from perforation of the shells or hulls of ships, we are greatly worse off in these days of steel and iron than we were when our ships were built of oak, teak and pine. Apart from the greater

Jan 1, 1891

By Forbes Wilson

IN February 1952 Freeport Sulphur Company started exploration work on a group of lateritic deposits at Moa Bay, Cuba. As a result of successful exploration work and a vast amount of metallurgical research over the past five years, these deposits will soon become a new Free World source of nickel and cobalt. Moa Bay lies on the north coast of Oriente Province, the easternmost part of the island, about 600 miles east of Havana and about 40 miles east of the U. S. Government nickel plant at Nicaro.

Jan 5, 1958

By Richard Moldenke

A. E. OUTERBRIDGE, JR., Philadelphia, Pa. (written discussion).¬ The fact that iron castings improve with age has long been known. Many years ago the late Sir Frederick Bramwell, a distinguished engineer, formerly in charge of the metallurgical and gun-making department of the Woolwich Arsenal, England, determined to break up a large number of cast-iron mortars of an obsolete type that had been in stock for years. It was then reported to biro that it was found to be much more difficult to break these old gun castings under the "drop" than it was to break similar gun-castings recently made, under his own supervision; he changed the.. composition of the iron and still found that whenever castings made recently were broken up (on account perhaps of superficial defects) great disparity was observed in apparent strength between the old and new castings. Sir Frederick then made many other comparative tests, such

Jan 4, 1917

By R. A. Vik, C. B. Daellenbach, W. M. Mahan

The influence of reduction roasting and thermal shock on the grindability of a refractory low-grade Michigan iron ore was examined in bench-scale tests. The quantitative effects of the various treatments were evaluated at three sieve levels, 48, 100, and 400 mesh, with ball-mill-grindability and work-index parameters as response indicators. Data from the testing program were statistically analyzed to isolate the effects of cooling rate, roasting temperature, mesh level, and ore chemical condition. All four variables were found to have an important influence on the grindability of the treated ore. Ore chemical condition and roasting temperature had the most pronounced effects.

Jan 1, 1972

By James E. Mills

In the work of exploring certain gold-bearing gravels in the American Valley, Plumas Co., California, entrusted to my charge by Prof. A. Agassiz, of Cambridge, and Q. A. Shaw, Esq., of Boston, it became necessary to sink a shaft through loose materials containing in some layers large quantities of water, and I have been compelled to devise a new method which has proved successful and may be of service elsewhere.

Jan 1, 1885