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YEAR OF ELECTION 1913. FRANK DAWSON ADAMS Montreal, Canada. 1921. WILLIAM CUTHBERT BLACKETT Sacriston, Durham, England. 1923.. GELASIO CAETANI Rome, Italy. 1920. HENRY STURGIS DRINKER Merion Station, Pa. 1921. FERDINAND FocH Paris, France. 1922. FEDERICO GIOLITTI Torino, Italy. 1906. SIR ROBERT A. HADFIELD London, England. 1921. FRANK WILLIAM HARBORD London, England. 1917. HERBERT HoovER Washington, D. C. 1905. HENRI LECHATELIER Paris, France. 1921. C. McDERMID London, England. 1913. EZEQUIEL ORDONEZ Mexico City, Mexico. 1909. ALEXANDRE POURCEL Paris, France. 1911. ROBERT H. RICHARDS Cambridge, Mass. 1891. DR. ING. H. C. EMIL SCHROEDTER Mehlem a Rhein, Germany. HONORARY MEMBERS (Deceased)

Jan 1, 1928

By Yong Kang, Renhuan Yu, Xinquan Liu, Liangying Chu, Qian Luo

In grinding-classification circuit, overgrinding, resulted from the fact that hydrophobic materials have higher density than hydrophilicmaterials, has been known as a knotty problem. By using of the air-sparged hydrocyclone (ASH) as classifier, in this pair, the overgrinding of hydrophobic materials has been successfully minimized. Compared with the conventional hydrocyclones, the ASH has less fine hydrophobic particles in the underflow and less large particles in the overflow, which shows that the recovery of fine hydrophobic particles in the overflow has been improved in the ASH.

Jan 1, 1995

By W Mahoney, F Clement, E Saraiva

Prefabricated waterproofing sheet membranes are extremely complicated to install in underground sections with complex geometries and, despite being already subjected to quality tests in the factory, the installed membrane often exhibits leakages due to different reasons. Main sources of leaks are the required high amount of welding seams and damages caused during installation of reinforcement, as well as overstretching and poorly installed secondary concrete linings. Also the design of the tunnel lining is strongly influenced and limited by the use of prefabricated waterproofing sheet membranes. The use of sprayed waterproofing membranes for more than a decade has contributed to durability and serviceability, as well as to increasing sustainability of tunnel linings. The presented sprayed waterproofing membrane MasterSeal 345 is an advantageous alternative to prefabricated waterproofing sheet membranes under typical tunnelling conditions, especially in geometrically complex areas, such as in lay-by niches, cross passages and crossover caverns, where installation of conventional waterproofing membranes is inherently difficult, and locating leaks is challenging. This membrane has been successfully used in underground projects with different waterproofing design concepts and under diverse hydro-geological and environmental conditions for over a decade. It provides tunnel designers with different options and optimisation for the design of the tunnel concrete lining. Additional advantages to owners, contractors and designers from the use of the sprayed membrane include flexibility in the design, increased productivity and flexibility in working programming, as well as improved logistics, resulting in significant program and cost savings and reduced long-term maintenance costs. This paper describes the key features of this sprayed waterproofing membrane, its application range and limitations, the waterproofing concept, design options and related benefits. Further, guidance for membrane application and quality control and a summary of two recent project references in the United Kingdom and in Switzerland are provided.CITATION:Saraiva, E, Clement, F and Mahoney, W, 2014. The use of sprayable waterproofing membranes in underground structures – concept, design options, benefits and limitations, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 323–332 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By N. Ono, H. Fujiwara, S. Otsuka-Yao-Matsuo, T. Omata

"The electrical conductivity and the oxygen release and uptake of sintered indium tin oxide (ITO) upon heating and cooling under the condition that P(O2)/P*=4.9X10-4 (P* = atmospheric pressure), :when P(O2) was approximately 50Pa, were simultaneously measured by using a closed-system oxygen-gas analyzer. A large increasing in -the electrical conductivity - upon the· oxygen release detected in 1130<T<1273K was observed. Quantitative relationship between the number of oxygen atom released from ITO and the conduction electron density in ITO was studied. The release of one oxygen atom agreed with the generation of two conduction electrons, i.e., the efficiency-carrier-generation for the oxygen release from the ITO was almost one. The oxygen atom released must be originally at the quasi-anion site in the C-type rare-earth lattice, i.e., the 16c site in the space group of Ia3, as an interstitial excess oxygen, Oi"". It was concluded that the mechanism of conduction carrier generation and compensation upon SnO2 doping into In2O3 can be expressed by the defect equation, 2SnO2-2Sn1n +2(1-z)e'+zOi""+3O0 x+(l-z)/2O2, and that the oxygen release bringing the increase in the electrical · conductivity can be expressed by the equation, Oi""-1/2O2+2e'.IntroductionThin films of SnO2-doped In2O 3 (generally designated as ITO, for indium tin oxide), which have high optical transparency for visible light and high electrical conductivity, have been used as transparent electrodes for liquid crystal and electrochromic displays. It is well known that the electrical conductivity of ITO depends on the content of SnOi-dopant and oxygen. However, a reliable relationship between electrical conductivity and the absolute oxygen content in ITO has yet to be reported. The elucidation of such a relationship is one of the important clues for realizing extremely highly conductive ITO electrodes."

Jan 1, 2000

By Y. J. Wang

The ventilation network problem, having both fixed and nonfixed operating points as control devices, is examined in this paper. Emphasizing the concept of solving a system of n equations in n unknowns, this paper presents the generalized problem formulation, some conditions under which the problem does not have a unique solution, and a solution procedure based on the Newton (or Newton-Raphson) method. A numerical example is included.

Jan 1, 1989

By Pierre Laliberté

Objectifs ?Quantifier les économies d?énergie potentielles liées àl?utilisation de différentes technologies ?Créer un modèle permettant d?évaluer les économies possibles d?énergie en combinant plusieurs technologies ?On ne peut simplement additionner les pourcentages d?économie individuels pour en évaluer le total.

Feb 1, 2008

Norton Co., the world&apos;s largest producer of abrasives, is enlarging its proppant operation. Proppants are strong chemical particles used to wedge open rock formations in deep oil wells, thereby increasing the well flow rate, sometimes as much as tenfold. Norton" aluminum oxide-based proppant is rapidly displacing less durable materials. The company is building the world&apos;s largest proppant plant in Fort Smith, AR. ALUMINUM--See also REFRACTORIES The price of primary aluminum ingot was increased by several producers in July. Kaiser Aluminum & Chemical Corp., and Revere Copper & Brass Inc. increased the price of primary aluminum to 63.0 cents per pound, effective July I. Reynolds Metal s Co., Anaconda Aluminum Co., Howmet Aluminum Corp., and Marti n Marietta Aluminum Inc. increased the price of 99.5% primary aluminum ingot to 63.0 cents per pound, effective July 5, The Aluminum Company of America increased the price of aluminum ingot to 62.5 cents per pound, effective July 9. The range of prices at the end of the month was 58.5 to 63.0 cents per pound.

Jan 1, 1979

By R. V. Higgins

A numerical method is presented to calculate the pressure distribution in a petroleum reservoir that has irregular boundaries. The computer program is straightforward and requires minimal data preparation. The method can also be used to determine pressure distribution in many other types of underground reservoirs. In this method, the grid solution of the fluid-flow equations in a reservoir that has regular boundaries (previously published) was expanded to handle irregular boundaries. The computer program locates grid points at the irregular boundaries. The method of mirror images is then used to form a special stencil to determine the pressure at each of these points. Two examples are presented to demonstrate the applicability of the method for virtually any reservoir configuration.

Jan 1, 1972

By Roman Šejnoha, Karel Mazanec

A pronounced tendency for delayed fracture zoas observed in the martensite structure of low-alloy steels in the as-quenched condition. Cracks of predominantly intercrystalline nature nucleated and propagated at stresses substantially lower than the short-titne tensile strength of- the steels, and were observed even in hydrogen-free speciunens. The occurrence of delayed fractures in the as-quenched condition is interpreted as a supevposition of the effect of free dislocations generated during the martensite transforlnation, and of a weakening of the prior austenite grain boundaries caused by dynamic shocks exerted on the boundaries by growing martensite plates. AN important metallurgical problem, connected with the production and use of high-strength steels, is delayed fracture in martensitic structures. Such fractures occur in quenched steels as a result of prolonged loading with external stresses far lower than the short-time tensile strength of the steel. The same effect can be produced by sufficiently high internal stresses: it is well-known that quenched structures will in some cases crack intergranularly at room temperature if not tempered quickly enough even in the absence of any externally applied stress. In Troiano&apos;s papers1,2 on delayed fractures in high-strength steels, the fundamental role of hydrogen migrating under the influence of multiaxial stress towards the nuclei of cracks was found. Fig. 1 shows the typical relationship between stress and the time to fracture found by Troiano in hydrogen-charged high-strength steels. On the other hand, Shurakov 3,4 explains the realization of delayed fractures in martensite as due to a "quasi-viscous" behavior of the austenite grain boundaries immediately after the martensitic transformation. 1) MATERIALS AND EXPERIMENTAL METHODS Two low-alloy steels of commercial purity were used for the experiments reported in this paper. Their chemical composition is shown in Table I. The heats were melted in a laboratory furnace, cast to ingots, forged to bars of 3/4 in. diameter, and annealed. Machined test pieces were heat-treated as follows: Ni-Cr-Mo steel held at 900°C for 30 min and quenched in oil; Mn-Si-Cr steel held at 900°C for 30 min and quenched in water. For the delayed-fracture tests, notched cylindrical test pieces, Fig. 2, stressed in torsion, and unnotched cylindrical tensile-test pieces, 1/4 in. diameter, were used. The specimens were normally loaded with a constant static load 45 min after quenching for the torsional tests and 10 min

Jan 1, 1965

By T. M. Gurr

Large quantities of phosphate rock are mined and processed in Central Florida (Figure 1). The phosphate rock from the mines is further processed in "chemical plants" to produce phosphoric acid (Figure 2). A by-product of the processing&apos; of the phosphate rock to produce fertilizer chemicals is an impure form of gypsum referred to as phosphogypsum. For each ton of phosphate rock processed, approximately 1.5 tons of phosphogypsum is produced (Figure 3). The typical method to dispose of this by-product gypsum is to stack it in large piles, locally referred to as gypsum stacks or gypsum fields (Figure 4). These gypsum stacks have been the focus of many studies in recent years in an attempt to identify the potential for ground water and/or air pollution associated with the stacks. This paper attempts to discuss some of the ground water impacts and current attempts to minimize these impacts.

Jan 1, 1990

By S. K. Schwartz

"This paper describes the general layout of the environmental monitoring scheme at Devco &apos;s No. 26 Colliery, including wall face ventilation, fan performance and methane drainage, and then goes on to discuss the sensors, the outstation layout, the surf ace control room and the protection of the system.IntroductionCape Breton coal mines have been pioneers in the use of the latest technology in mining coal on this continent. To mention just one example, continuous methane monitoring at the coal face was started in 1976 and the idea of automatically stopping the face conveyor during high gas levels using the face signalling system was conceived and developed by CBDC engineers.With the introduction of remote environmental monitoring, No. 26 Colliery will be the first underground coal mine in Canada and possibly in North America to have computer-based comprehensive environmental monitoring.Traditionally, surveillance of the mine environment has been based mainly on periodic checks by portable or hand-held monitors. Although this method proved adequate, it has some limitations, namely:1) restricted &apos;number of observations and samples;2) relatively long time between taking measurements and availability of results for assessment.With remote monitoring, the above limitations are overcome because (a) monitoring is continuous and (b) monitored data are updated quickly (typically 5-7 sec.). Remote monitoring also provides a centralized &apos;information center&apos; at the surface from where the entire mine environment can be monitored. Details of modes in which data can be displayed and features available at the location will be discussed later in the paper."

Jan 1, 1982

By Suzann C. Ambrosio

The mineral industry in Burundi continued to be a minor contributor to the 1980 gross domestic product (GDP) estimated at $293 million in constant 1970 prices.2 Mineral export revenues, primarily from cassiterite, increased by a factor of 15 between 1979-80, reaching approximately $434,000 by yearend 1980. Gold, bastnasite, colombite-tantalite, and wolfremite continued to be exploited on a small scale, using manual and semimechanical methods. Despite a sharp decline in mining activities during 1979, attributed to a lack o? profitability and shortage of construction materials, the mining sector exhibited signs of recovery during 1980. The mineral exploration budget grew 32% over 1979 levels and was equivalent to approximately $42,000 in 1980. In addition, the Burundi Geographical Institute (IGE BU) was created in September 1980 and given responsibilities to collect cartographic, topographic, hydrogeologic, and other geomorphological data., SONIBUROM, the Burundian and Romanian Government joint mineral corporation, conducted mineral deposit inventories during 1979-80 and has been charged with exploiting some of these as yet unspecified resource areas. Another Burundian-Romanian effort, called Mabaya-Butahana, was initiated to search for gold deposits. Meanwhile on the Ruzizi plain, alluvial gold prospecting, with an estimated grade between 0.2 to 1.0 gram per ton, was carried out on a small scale.

Jan 1, 1982

By M. J. Hrebar

A study was conducted to evaluate the applicability of large wheel loaders (Cat 994 class) as primary loading equipment in open pit iron ore operations. Field visits were made to taconite and gold mines that used large wheel loaders. Data were gathered on loader selection rationale; operating and maintenance experience; and production, availability, and cost information. Brief time studies were conducted to indicate machine performance and utilization. The paper summarizes the field data and includes economic comparisons of wheel loaders versus cable shovels in an iron ore application.

Jan 1, 1996

This is a welcome opportunity to exchange ideas about educating for a profession in mining and metallurgy, and I shall use it to highlight the ways in which educators, the industry, and the profession can help one another make that educa- tion better. This is home ground for me in more ways than one. As the executive head of a uni- versity perhaps I may speak as an educator; and there is still, I hope, enough of the metallurgist in me to allow me to speak of what we metal- lurgists and mining engineers can do to help the educators. Another interest should be declared, too. Among the educating agencies I shall focus on universities; among universities I shall further focus on my own, the University of New South Wales. I know it best; and, more to the point, we are one of the minority that offer a full profes- sional training in mining and metallurgy. Further, we are as a university very much concerned- more than most-with specifically professional education, and especially with education in the professions based on science and technology. Mining and metallurgy have of course played a central role, from earliest times onwards, in the history and development of science and tech- nology. In that role they have been both pro- ducers and consumers of new knowledge. Indeed the whole new attitude to knowledge that began to spread in 16th and 17th century Europe owed a great deal to the interests and traditions of the miner and the metallurgist. The first modern text- book of mining and metallurgy, George Agricola&apos;s De Re Metallica, is very much more than a spec- ialist handbook; it is a major landmark in intel- lectual and cultural history.

Jan 1, 1978

By H. C. Horwood

INTRODUCTION THE Argosy Gold Mines, Limited, which joined the ranks of active Ontario gold producers during the summer of 1936, holds a group of 21 claims on Casummit lake, in the Patricia portion, district of Kenora, northwestern Ontario. The Company is developing and mining goldbearing quartz veins that occur in a series of greywackes and slates of probable Keewatin age. The writer made a geological examination of the property and the surrounding area for the Ontario Department of Mines during the early part of the field season of 1936. This paper is a report on the general geology, structure, and ore deposits at the mine and is based almost entirely on data compiled during the examination. HISTORY Mineralization was first discovered on the property in May, 1929, by A. F. Hewitt, who, with J. A. Borthwick, decided that the country had prospecting possibilities and commenced work in April. Mr. Hewitt staked, and with his partner, J. Ziyone, still holds the group of claims lying immediately east of the present Argosy holdings. Mr. Borthwick staked six claims, K.R.L. 9,681 to 9,686, inclusive, adjoining Hewitt&apos;s on the west and later added claims K.R.L. 9,733 to 9,740, inclusive, to his holdings. F. Fiskness, who was also prospecting in the region, discoveted No. 1 vein on Borthwick&apos;s claims, and with his two partners, L. Parth and H. Jones, staked claims K.R.L. 9,758 to 9,763, inclusive, to the northwest of Borthwick&apos;s and Hewitt&apos;s ground. In July, 1929, the Casey Mountain Operating Syndicate, which held ground to the northwest, secured an option on Borthwick&apos;s claims. The Fiskness-Parth-Jones property was added in January, 1930, to protect the west dip of the veins. During the winter of 1930-31, the veins were explored by diamond drilling, No. 2 for a length ?of 900 feet and a vertical depth of from 51 to. 375 feet? and No. 3 .t~ a slope depth of 175 feet. I~ August, 1.931, after the msrallat10n of a miming plant, the Casey Summit Gold Mmes, limited, was incorporated to take over the property from the Syndicate. The Maple leaf Mines optioned a controlling interest in the stock in August, 1933, and on September 17th, 1934, brought a 50-ton amalgamation mill into production. From early in October to December 27th, 1934, when the mill was closed down, 4,094 tons of ore were treated to yield 887.89 ounces of gold and 87 .26 ounces of silver( ! ).

Jan 1, 1937

Jan 1, 1917

By Robert B. Parsons

"The Whitehorse Mining Initiative (WMI) brought together all of the key stakeholders in Canada&apos;s mining industry to develop a framework whereby the industry can meet the challenges that it faces into the 21st century. The WMI Accord7 which was signed at the annual Mines Ministers Conference in Victoria, British Columbia, on September 137 1994, touches all of the important issues that confront the industry, including taxation. IntroductionSeptember 13, 1994, was a historical day for Canada&apos;s mining industry. On that day, on the occasion of the annual Mines Ministers Conference in Victoria, British Columbia, the Whitehorse Mining Initiative (WMI) Accord was signed by the leaders of the five principal stakeholders in the industry: industry; government; labour; environmentalists; and aboriginals. The Accord is the culmination of two years of hard work and intense collaboration by these stakeholders. But, the Accord is not the end result. The Accord can better be described as a springboard to a prosperous future for mining in Canada.The WMI had its beginnings at the Mines Ministers Conference in Whitehorse, Yukon, in September 1992 (hence, the name of the initiative). At that time, the mining industry was well aware of the serious challenges facing the industry, including significantly increased competition for mineral investment from other mining countries, coupled with an atmosphere of uncertainty surrounding land access, environmental regulations, and taxation. The diversion of investment abroad was hurting, and would continue to hurt, all Canadians. Something had to be done. At the 1992"

Jan 1, 1994

By J. L. Huisman, G. Schouten

After pyrometallurgy and hydrometallurgy, bio(hydro)metallurgy is the latest development in the ongoing search for efficient and economic metal winning processes. In addition to bioleaching, other biotechnology-based applications are getting more and more accepted. In this paper a number of proven and commercial processes will be presented that can be applied for nickel and cobalt recovery and refining. These processes are based on the ability of biomass to convert the redox state of sulphur compounds under ambient conditions. They can be applied to recover sulphate from effluents or SOx from off gases and convert it to H2S or dissolved sulphide that can be reused in production or effluent treatment. Not only does this minimize the costs on resources but it also reduces waste production and improves the quality of discharges even to the point where reuse becomes feasible.

Jan 1, 2005

By Robert Ammon

The purpose of this paper is to present a brief sketch of the development of this hindered-settling classifier, but primarily to show the actual results obtained in practice with the classifier working on the Butte copper ores at the Boston & Montana Concentrator at Great Falls and the Washoe Concentrator at Anaconda. The writer has endeavored to be as brief as possible, giving only the essential figures showing the efficiency of the classifier and leaving considerable interesting information to be derived by the reader from the statistics given. The paper deals with the practical work of the classifier under the following heads: 1. Desliming 4.0-mm. primary feed, overflow from 0.07 to 0.0 mm. 2. Desliming 1.25-mm. secondary feed, overflow from 0.07 to 0.0 mm. 3. Desliming Huntington Mill discharge, overflow from 0.07 to 0.0 mm. 4. Classifying 2.5-mm. deslimed secondary feed, overflow from 1.00 to 0.07 mm. 5. Classifying 2.5-mm. deslimed primary feed, overflow from 0.75 to 0.07 mm. 6. Classifying 4.0-mm. deslimed primary feed, overflow from 0.75 to 0.07 mm. 7. Classifying middling-tailing product from roughing tables, overflow coarse tailing. 8. Classifying 2.5mm. trommel undersize, not deslimed, overflow from 0.75 to 0.0 mm. 9. Remarks on the inner feed cone. In the following pages all overflows are given in quartz dimensions; i. e., by a 0.75-mm. overflow is meant an overflow whose maximum particle is a 0.75-mm. quartz grain. By the term "slime" is meant all material which will pass through a 200-mesh screen whose average opening is 0.07 mm. The development of the classifier was commenced in the fall of 1910,

Jan 1, 1914

By C. S. Liao, S. L. Wang, C. H. Yan, F. X. Cheng

A significant development in the theory of countercurrent extraction will be presented in this article. A new term in countercurrent extraction process analysis, "Adjacent Stage Impurity Ratio" (ASIR), is proposed, and its expression is deduced. Furthermore, based on the term together with mass balance and extraction equilibrium, the conditions where a given countercurrent extraction separation operation can have minimum amounts of both extracting solvent and scrubbing agent solution can be estimated, and the equations of the two minimum amounts can be deduced. It was found that the equations for a two-component separation using a single aqueous or organic feed are exactly the same as they appeared in the theory initially established in the 1970s. Unlike its earlier version, the present derivation does not involve feed-stage-composition hypothesis, and also has the advantage of dealing with a double-feed system where both aqueous and organic feeds are simultaneously employed whereas the earlier theory can only analyze a separation using a single aqueous or organic feed.

Jan 1, 2014