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By J. van der Merwe, D. Tharandt

The corrosion behaviour of 304L stainless steel laser-cladded with various amounts of ruthenium (Ru) was evaluated in solutions of sulphuric acid and sulphuric acid plus sodium chloride at 25°C and 45°C by open-circuit potential and cyclic potentiodynamic polarization tests. In general, the addition of Ru to the stainless steel increased its corrosion resistance in 1 M H2SO4, as well as in 1 M H2SO4 plus 1 wt% NaCl. This was observed for a number of parameters such as corrosion rate, corrosion potential, open-circuit potential, and current density. However, increasing the amount of Ru added beyond a certain level did not result in further improvement in corrosion protection. For each environment there is an optimal Ru concentration for the best corrosion protection. For example, in 1 M H2SO4 at 25°C, 2.44 wt% Ru shows the least active surface in terms of corrosion. Further research into ruthenium coatings on stainless steels is recommended.

Jan 1, 2015

By A. J. Hendron, J. E. Monsees

INTRODUCTION This paper is the outgrowth of work done by the authors to prepare the seismic design criteria for underground structures on the Southern California Rapid Transit District (SCRTD) Metro Rail Project. It is a follow-on to a similar paper presented at the October, 1984, ASCE National Convention (17). For design, the earthquake-induced distortions recommended herein are to be added to the normal static loading conditions for the underground structure. This design approach has been used by 18 section designers on the SCRTD Project. Preliminary results from two- and three-dimensional finite element solutions have partially verified the approach. Areas where additional research is needed for special cases are identified. EFFECTS OF EARTHQUAKE The effects of earthquakes on underground structures may be broadly grouped into two general classes -shaking and faulting. In response to earthquake motion of bedrock (shaking) , the soil transmits energy by waves. Seismologists identify various types of earthquake waves, but underground engineers are generally interested in the effects of transverse shear waves which produce a displacement of the ground transverse to the axis of wave propagation. The orientation of propagation is generally random with respect to any specific structure. Waves

Jan 1, 1985

By H. Meseck

Dynamic pile test methods to establish the bearing capacity of driven piles were developed in the USA more than 20 years ago. In the Federal Republic of Germany, the first dynamic pile tests were carried out at the end of the 70's. Today dynamic pile tests are successfully used to establish the integrity and bearing capacity of driven and bored piles. The Institute of Foundation Engineering and Soil Mechanics at the Technical University of Braunschweig has developed its own method of measuring and evaluation for the execution of dynamic pile tests. The principles of the dynamic pile tests, the measuring and evaluation plant as well as the experience gained with it in the examination of cast-in-place piles are presented in this contribution.

Jan 1, 2010

By Robert B. Hopler

The hazards which naturally prevail in underground coal mines, always severe and unpredictable due to the loosely-consolidated strata in which coal is frequently found, are increased by the commonly-occurring combination of coal dust, methane, and explosives. It was recognized by the mid-nineteenth century that coal dust was the basic factor contributing to disastrous explosions killing hundreds of miners, and that the ignition of methane gas was often the source of the coal dust explosions. It was apparent that preventing the ignition of methane was a critical part of avoiding these disasters, and it was also apparent that one cause of such ignitions was the firing of explosives. In addition, it was found that dust explosions were often initiated by blown-out shots of explosives in the absence of methane.

Jan 1, 1996

By A. A. Goss

We investigate the relationship between corporate financial performance (CFP) and environmental and social performance (CSP) in a sample (n=165) of large, publicly traded U.S. mining and oil and gas firms. Using optimally scaled principal components analysis to generate aggregate measures of CSP strengths and concerns, we find higher concerns are related to higher volatility of unexpected earnings and discount rates. Furthermore, these earnings shocks are more likely to be negative as concerns increase. Decomposing this relationship shows that negative environmental performance dominates proactive environmental management as a driver of unexpected earnings, but proactive community efforts increase the magnitude of earnings shocks. We document some evidence of the strategic use of CSR, with those firms that have greater risk investing more proactively in CSR.

Aug 1, 2013

Pillars in underground limestone mines are required to support the overburden and provide a safe, stable working environment for mining personnel and equipment. Pillar stability was assessed by the National Institute for Occupational Safety and Health in underground limestone mines in the Eastern and Midwestern United States. It was found that current mine layouts have been successful in providing support to the overburden, while a small number of isolated pillar failures were observed. The stable pillar layouts and failed pillars were plotted on a chart that demonstrates the relationship between pillar width-to-height ratio and pillar stress. The results show that pillar failures occurred at the lower range of width-to-height ratios and can occur at relatively low stress levels. Zones indicating the potential risk of pillar instability are shown on the chart, based on hazards associated with the onset of rib spalling, large angular discontinuities and unconfined pillars. The chart can assist limestone mine planners to evaluate potential instability in current or new pillar layouts that are similar to those included on the stability chart.

Jan 1, 2008

By Herbert Hoover

I HAVE been greatly honored as your unanimous choice for President of this. Institute, with which I have been associated during my entire professional life. It is customary for your new President, on these occasions, to make some observation on matters of general interest from the engineer's standpoint. The profession of engineering in the United States comprises not alone scientific advisers on industry but, in great majority, is comprised of the men in administrative positions. In such positions, they stand midway between capital and labor. The character of your training and experience leads you to exact and quantitative thought. This basis of training in a great group of Americans furnished a wonderful' recruiting ground for service in these last years of tribulation. Many thousands of engineers were called into the army, the navy, and civilian service for the Government. Thousands of high offices were discharged by them with credit to the profession and the nation. We have in. this country, probably, one hundred thousand professional engineers. The events of the past few years have greatly stirred their interest in national problems.' This has taken practical. form in the maintenance of joint committees for discussion of these problems and support to a free advisory bureau in ,Washington. The engineers want nothing for themselves from Congress.. They want efficiency in government, and you contribute to the maintenance of this bureau out of sheer idealism. This organization for consideration of national problems has had many subjects before it, and I propose to touch on some of them this evening.

Jan 1, 1920

By D. F. Hambley

This report documents the work carried out by Engineers International, Inc. and its subcontructor, W. G. Pariseau, in order to develop a design manual for ore passes for open pit mines. The work included an extensive information search, novel analyses in rock flow theory, cost and time estimation for shaft and raise construction methods, and development of design criteria for the are pass proper, dump point, and draw point.

Jan 1, 1983

By Haydn H. Murray

Kaolin is defined and described as an industrial mineral. In addition the types of deposits -primary and secondary are defined and the genesis of kaolin from feldspars and other minerals discussed. The major deposits of the world found in the United States, Great Britain, Brazil, and Czechoslovakia are described along with many of the minor kaolin deposits. Four areas which have very large deposits of kaolin could, with technological breakthroughs to reduce viscosity significantly, become important factors in supplying the world markets which are increasing year by year.

Jan 1, 1977

By Allen L. Frank

The uranium mine environment is characterized by airborne radon-222 and its daughter products to which miners are exposed through breathing and by gamma and X rays from the uranium-235 and uranium 238 chains to which the miners are exposed externally. The nature of the radon-daughter concentrations and the methods used to define and measure the exposures are explained through an extensive review of the literature. An improved passive track-etch dosimeter for personal use is proposed which has a measurement range of about 30-400 WLH with a 95% confidence interval to ~25% for individual detector measurements in relatively stable mine air. Some measurements of these dosimeters adapted to environmental use are also presented. A program of development for enhancement of dosimeter sensitivity and greater accuracy of measurement is outlined. Extensive gamma-ray survey measurements were made in two Colorado and three New Mexico mines. Follow-up personal miner dosimetry with LiF TLDs was done at the mine with the highest exposure rates, The average miner exposure rate measured was 4.27 mR per day, or 9.3 of the maximum permissible level averaged over 13 weeks. Comparisons are made with previous mine surveys and their value in estimating miner exposure is discussed. Some depth-dose measurements made using Lucite as the absorber are evaluated.

Jan 1, 1978

By Ralph H. Espach

Wyoming contains many petroleum and natural-gas fields, and more than 250 geological structures have been mapped; however, only about 85 have been found (July 1938) to contain petroleum or natural gas, or both, in commercial quantities. To January 1938 approximately 434 million barrels of oil and 915 billion cubic feet of gas have been produced, and it was estimated that proved oil reserves in Wyoming amounted to 300 million barrels.' The Salt Creek field, the largest in the Rocky Mountain area, alone has produced 64 percent of the State's oil and 46 percent of its gas. This field ranked thirteenth among the producing fields of the United States in total cumulative production as of January 1, 1938. On this basis it ranks with the Kern River and Huntington Beach fields of California and the Butler County fields of Kansas. The Salt Creek field has declined in relative importance; in 1937, while still the largest oil-producing field in the State, it produced 31 percent of the oil and 11 percent of the gas extracted from all wells in Wyoming.

Jan 1, 1941

The Yanacocha Project is the first foreign investment in Peruvian mining since Cuajone (1976). Three years after the project began, it has become the largest producer of gold from heap leach operations in the world and the top producer in Latin America. The success of Minera Yanacocha (MYSA) opens a new chapter in Peruvian mining with the exploitation of its widely spread gold deposits and has attracted the interest of foreign investors in Peru's ample mineral resources. Construction began on August 1, 1992 and after twelve months of arduous work, the first gold bar was poured on August 7, 1993 from ore from the Carachugo mine. In 1993, Minera Yanacocha produced 81,000 ounces of gold and 304,000 ounces in 1994 (40% above budget). Production is expected to exceed 500,000 ounces in 1995 with the start-up of operations in the Maqui Maqui mine. This paper presents a summary of MYSA's experiences during its first two years of operations in the areas of mining, ore processing, environmental protection, loss control and community assistance. The paper also shows that MYSA's successes are not only due to the richness of the deposit, but also to the combination of a number of factors basic to the project's success, such as: an economic policy favoring investment in Peru, the availability of highly qualified local personnel to facilitate the transfer of technology from the United States and the desire and determination of the partners to carry the project forward in an initial atmosphere of uncertainty and terrorism.

Jan 1, 1996

By Don Welch

Pressures for change ?Land use constraints ?Project financing ?Local communities ?Environmental issues ?Sustainability requirements ?Stricter regulatory procedures ?Technical excellence ?Reduce risk ?Impacts of failure & non-compliance

May 1, 2010

[Pumps: oil-well: plunger: essential parts, G26, 130; 74, 828 improved type, 74, 846 leakage, 74, 837 operating cycle, 74, 833 Uren design, G26, 145 sucker-rod failures, G26, 136 sucker-rod stress, 74, 835 sucker rods, 74, 830, 832 tubing, 74, 833 tubing difficulties, G25, 138; 74, 836 Olivite, 73, 337 valve and seats, 74, 832 Punching: Monel metal, 78, 86 nickel, 78, 86 Punjab. See Indian Empire. PUPIN, M. L biography, M26, 113 John Fritz medalist, 1931, M81, 499 recipient of Washington Award, M28, 155 PURDY, R.: Discussions: on Relative Efficiencies of Domestic Fuels in Relation to Their Costs and Their Advantages 108, 353 on Uses on Coal in the Ceramic Industry, 108,389,398]

Jan 1, 1936

By S. A. Allen

The Eufaula bauxite district of Barbour and Henry Counties in southeast Alabama covers an area approximately 14 miles long, 6 miles wide at the eastern extremity near the Chattahoochee River, and 10 miles wide at the western end near the east fork of the Choctawhatchee River (see figs. 1 and 2). The long axis of this polygon bears a little south of east.

Jan 1, 1949

By Joel Lööw, Jan Johansson, Lena Abrahamsson

Industry 4.0 offers new possibilities to combine increased productivity with stimulating workplaces in a good work environment. Used correctly, digitalization can create attractive jobs in safe control room environments, which provide space for the employee’s full expertise and creativity. This is true also for the mining industry. But, to succeed, it is important to analyze the development from a worker’s perspective. What will happen to their work? What skills will be needed in the mine of tomorrow? We must also consider the risks, such as privacy issues, increased stress, and work-life boundaries. These questions must be understood if we are to create workplaces that can attract a young and diverse workforce to tomorrow’s mining industry. In this article, we try to illustrate what the new technology can mean for the individual miners. We formulate the notion of Mining 4.0 (Industry 4.0 in the mining industry), where we try to create an image of how the future might look from a miner’s perspective and how mining companies may navigate their way to a future that works for all miners. To illustrate the range of possible outcomes, we formulate two scenarios: one utopian and one dystopic. At the end of our article, we bring forward six recommendations that can be considered a beginning of a road map for the human side of Mining 4.0.

By Joel Lööw, Jan Johansson, Lena Abrahamsson

Industry 4.0 offers new possibilities to combine increased productivity with stimulating workplaces in a good work environment. Used correctly, digitalization can create attractive jobs in safe control room environments, which provide space for the employee’s full expertise and creativity. This is true also for the mining industry. But, to succeed, it is important to analyze the development from a worker’s perspective. What will happen to their work? What skills will be needed in the mine of tomorrow? We must also consider the risks, such as privacy issues, increased stress, and work-life boundaries. These questions must be understood if we are to create workplaces that can attract a young and diverse workforce to tomorrow’s mining industry. In this article, we try to illustrate what the new technology can mean for the individual miners. We formulate the notion of Mining 4.0 (Industry 4.0 in the mining industry), where we try to create an image of how the future might look from a miner’s perspective and how mining companies may navigate their way to a future that works for all miners. To illustrate the range of possible outcomes, we formulate two scenarios: one utopian and one dystopic. At the end of our article, we bring forward six recommendations that can be considered a beginning of a road map for the human side of Mining 4.0.

By H. F. Yancey

The investigations described in this bulletin are confined to a study of the washing characteristics of bituminous coals. The major part of the work was conducted by the Bureau of Mines in cooperation with the Engineering Experiment Station of the University of Illinois and the State of Illinois Geological Survey Division between 1918 and 1924, in accordance with the provisions of an agreement between these agencies. The washing characteristics of coals from many of the important coal-producing fields of the Eastern and Central States were examined. The coals of the Pacific Northwest States and Alaska have been studied separately by McMillan and Bird of the Northwest Experiment Station of the Bureau of Mines at Seattle in cooperation with the College of Mines of the University of Washington.2 OBJECT OF INVESTIGATION The object of the investigation of coal preparation by the Bureau of Mines has been to promote the production of better prepared coal and to facilitate the correct selection and design of coal-preparation plants by obtaining as complete information as possible regarding the washability of the various types of American coals and the treatment best suited to each. In addition, some attention has been given to the development of new methods of washing coal. The work naturally divides itself into three rather distinct steps: (1) Development of a systematic method of examining and testing a coal; (2) classification of the American coals on a basis of the occurrence of the impurities associated with the coal in the beds; (3) examination of one or more representative coals of each type.

Jan 1, 1929

By A. J. Kraemer

This paper is the second and concluding report of the results of the twenty-fourth semiannual survey made by the Bureau of Mines of motor gasoline marketed in the United states. The first report on this 1931 survey gave the results of the examination of the gasoline samples in accordance with the new Federal specification for United States Government Motor Gasoline. The present paper reports results of the examination of the gasolines for color, doctor test gravity, end point, per cent recovered copper-dish gum, and steam-oven gum. The retail price and the tax at the time each sample was taken are also reported.

Jan 1, 1932

By James Westfield

Drilling for roof bolting has created a new dust problem for the coal-mining industry. Drilling is inherently dusty, and control of dust produced by drilling vertical or nearly vertical holes is much more difficult than control of that produced by drilling flat or down holes.4/ Also, the dust produced by roof drilling differs in composition from that produced by drill-fur, or cutting the coal face because it contains a significantly greater amount of free silica and therefore presents a greater potential hazard of silicosis. Roof bolting has been practiced successfully in the mines of the St. Joseph Lead Co. in southeastern Missouri for over 20 years, but it was not until 1947 and 1948 that large-scale roof-bolting experiments were conducted in coal mines.5/ Although the need for dust control in conjunction with roof drilling was recognized from the beginning, the development and acceptance of roof bolting progressed so rapidly during 1949 and 1950 that solution of the dust problem lagged behind other engineering phases of the technique.

Jan 1, 1951