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By B. Hyatt, E. Klokholm

The reesistivity of Cu-Pd alloys of 9.6 to 29 pct Pd alloys was measured after plastic deformzation in tension. For all compositions a continzting decrease in resistivity with increasing plastic strain was observed. By comparison with the results of Damask on a brass ad Cu3Au, it was deduced that these anonzalous decreases in resistivity are due to the decrease in short-vunge order caused by cold work. An anomalous decrease in the resistivity of cold-worked CU-Pd alloys was first reported by Jaumot and Sawatzky.' They observed decreases in the electrical resistivity when disordered Cu-Pd alloys drawing at room temperature. Recently, a similar anomaly was reported by Aarts and Houston-Mac-Mi1lan2 in Ag-Pd alloys containing 10 to 45 pct Pd. The plastic deformation in this case was produced by tensile strain at liquid-nitrogen temperatures. For AE-Pd alloys the relative resistivity change becomes positive for tensile strains of about 20 pct.

Jan 1, 1960

By Dhawan AK

On 8 July 1993, a landslide of about one million cubic metres of rock blocked the river Satluj near Sanjay Vidyut Pariyojana - Bhaba project and caused flooding into the Bhaba Power House (120 MW) resulting in suspension of power generation. The concerned authorities desired an early removal of the blockade by an underwater blasting operation into the over topping water to reduce the water level at the blockade and resume power generation in the power house. In the absence of underwater drilling, it was essential for the blasting technique to be used where no cavity to confine the explosive was required. For this reason mud capping and plaster shooting with directional throw were used and additional specially fabricated mild steel pipe charges were used under high current for an underwater trenching operation. By employing these techniques the river blockade was removed up to the required depth and on 8 September 1993 the Power House resumed the power generation.

Jan 1, 1995

By E. P. Peleider

DIAMOND drill research work was initiated at the School of Mines, University of Minnesota, in late 1949. The Drilling Symposium held in Duluth that spring highlighted the problem of high cost and core recovery and the need for controlled testing. An advisory committee made up of informed representatives of both mining companies and drilling companies was formed to suggest and advise on a program of drill research. A Hy-Mac hydraulic drill unit, see Fig. 1, especially designed for experimental testing, was obtained for this work by the School of Mines through the courtesy of the Carboloy Co. It is an extremely flexible unit, capable of exerting a forward thrust of about 1750 lb and turning at speeds from 650 to 2200 rpm. The feed arrangement is so designed that the advance can be set either at a constant rate or permitted to vary at a fixed Pressure, see Fig. 2. The

Jan 1, 1953

By Ishikawa K, Kikuchi T, Tokairin Y

Roadheader, developed from coal cutting machines, is generally classified as a tunnel excavation machine for soft rocks in respect to excavation mechanism, machine structure, weight, engine output and so on. In recent tunnel works, however, there is an increasing demand for changing from blasting to mechanical excavation by roadheaders to avoid environmental problems such as noise and vibration. But there exist various difficulties in excavation of harder rocks by roadheaders. In order to explore the possibilities of roadheader excavation, we performed field and laboratory experiments. In the field experiment, roadheader model S-125 (Mitui Miike Machinery Co.,Ltd.) was tested for various rocks of wide range of hardness, and excavation capacity and wear of picks were measured. In the laboratory test, cutting performance of the picks was tested by our cutter testing machine. This report describes thr: of these experiments and discussions :n possibility of applying boom-type tunnelling machines to hard rock excavation based on these experimental data.

Jan 1, 1987

Provide a method for obtaining in situ measurements of coal cutting forces which are needed for mining machine design. Approach A portable in-seam testing device is carried to the face of an underground coal mine heading to measure the cut-ting force encountered by a continuous miner pick directly at its maximum depth of cut. How It Works The tester frame is attached directly to the coal surface with four one inch diameter threaded studs resin-bolted into 1-1/4 inch diameter holes which are drilled 30 inches deep. Spherical nuts and washers compensate for misalignment between the bolts bearing plate, and traverse beams. Spacers can be placed over the studs to assure that the traverse beams remain in the same plane. Cutting forces are applied by a hydraulic cylinder that moves the pick of the tester through a twin-chain arrangement which gives a 20-inch cutting stroke with

Jan 1, 1982

By John W. King, S. Ralph Austin

Spurred by recent forecasts of greatly increased demands for uranium by 1980 and beyond, interest is once again focusing on America's western uranium deposits. One of the principal producers in this area is the Gas Hills district in Wyoming, the site of approximately 12% of the known uranium in the U.S., including past production and current reserves. Located on the south flank of the Wind River Basin, the Gas Hills deposits have been recently studied by the Atomic Energy commission for clues to and guides for discovering similar-occurring ores. The ore deposits are confined to a permeable sandstone unit, up to 350 ft thick, at or near the base of the upper Wind River formation of early Eocene age. The uranium occurs in three principal north- south "ore trends," each of which is about six miles long, one mile wide, and separated from each other by approximately three miles (Fig. 1).

Jan 5, 1966

By James Wang

In July 2003, The Office of Hydrogen, Fuel Cells and Infrastructure Technologies of the Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy solicited Grand Challenge Proposals to establish three Centers of Excellence in hydrogen storage developments for reversible metal hydrides, non-reversible chemical hydrides and carbon storage materials, respectively. The program mission is to research and develop cost-effective, on-board hydrogen storage systems that enable a minimum range of 300 miles within the weight and volume constraints of the vehicle. Currently, no hydrogen storage technology available can meet the DOE cost and performance targets. In April 2004, Sandia National Laboratories was selected by DOE to lead the Metal Hydride Center of Excellence with partners from 5 other national laboratories. We will present the organization and recent accomplishments of the Metal Hydride Center which is confident to accomplish DOE/FreedomCAR and Fuels Partnership objectives for 2010 in hydrogen storage for vehicular transportation applications.

Jan 1, 2006

By R. V. Ramani

Managers need quality information for effective decision making. This demand, at the present time, is being fulfilled by the increased use of computers via information systems, decision support systems and management information systems. The idea of incorporating intelligence into computers to aid decision-makers has been evolving for over two decades. In recent years, significant progress is reported on applications to business and sciences. In engineering functions, the Artificial Intelligence approach that seems to have great potential is the application of Knowledge Based Systems. The primary objective of this paper is to identify domains in mining engineering where application of knowledge based systems could be beneficial. In- corporation of the expertise required during the analysis and interpretation stages of an engineering design problem through knowledge based systems is recognized as an area of significant benefit. To this end, the components of knowledge based systems for mine ventilation and strata control design are described. The potential applications and limitations of knowledge based systems are outlined.

Jan 1, 1987

By W. L. McMorris, A. H. Brisse

IN the last several years the coal industry has intensified its effort to solve the growing problem of cleaning and recovering fine mesh coals. On one hand there has been increasing civic pressure for cleaner streams, and on the other hand there has been increasing production of fine mesh coal, resulting directly from adoption of the modern mining methods so essential to the economy of the coal mining industry. Cleaning fine coal with the same precision possible with coarser coals is a difficult task, and for coals finer than 200 mesh it has been impractical. Furthermore, the inclusion of -200 mesh material in the final product markedly increases costs of dewatering and thermal drying, which are necessary steps if coal is to meet market requirements. Consequently these extreme fines have generally been wasted. As a result, problems have been created in many districts because there has not been enough area for adequate settling basins.

Jan 2, 1958

By Zainelabdin Khalid Zainelabdin Elfaki

The influence of partially replacing cement with marble waste on the workability and compressive strength of concrete bricks was investigated. Three replacement percentages, 10%, 20% and 30% weight marble waste, were used with different curing times of 7, 14 and 28 days. Two specimens were prepared for each percentage and curing time. For this study, marble powder from the Mining House Company in Saudi Arabia was used. It was observed that the replacement of cement in Concrete brick with marble waste enhanced the loading strength and the workability of the prepared concrete bricks. It was also observed that 20% replacement of cement with marble waste was the best replacement percentage compared to the other replacement percentages tested. Marble waste from manufacturing companies, either in powder, sludge or slab form, has negative impacts on the environment. In contrast, reusing marble waste has both economic benefits (i.e., selling the marble waste) and lessening the need for raw resources.

Jan 1, 2014

By Frederick A. Mumpton

For more than 200 years zeolites have been familiar minerals to geologists and mining engineers as minor, but ubiquitous constituents in vugs and fractures of most basalt and traprock formations. More than 35 different species have been recognized including several, such as chabazite, erionite, mordenite, and faujasite, whose adsorption properties rival those of many synthetic molecular sieves. Igneous occurrences of this type have never been mined on a commercial scale; they are generally small and low grade, and they commonly contain as many as four zeolite minerals, along with small quantities of calcite, quartz, and other silicate minerals. Their economic beneficiation to monomineralic zeolite products has also not been achieved and, for the most part, industrial applications of zeolites have relied primarily on synthetic molecular sieves that were crystallized from hydrous aluminosilicate gels. During the middle 1950s, when Union Carbide Corp. and other groups were developing processes and markets for their fledgling synthetic zeolite businesses, natural zeolites

Jan 1, 1975

Provide mine operators with a quick means of identifying the effect of cutting system changes on relative dustiness at the mine face, by developing an interactive computer program for drum-type coal mining machines. Approach A program which simultaneously evaluates machine parameters, coal seam parameters and mine operator-controlled parameters for their effects on relative dustiness has been developed for use on any minicomputer using BASIC computer language. How it works The interactive computer program allows mine operators to make one or more changes at a time to their cutting system to determine how these changes affect relative dustiness of the face. Using this program, mine operators can find the optimum cutting system configuration to minimize dust using their seam conditions and their equipment specifications. The mining machine variables include: number of vane bits, number of gage bits, number of starts, vane wrap, number of end ring lines, rpm, advance rate, ton/min, percentage of time spent cutting per shift, and airflow.

Jan 1, 1986

By Newell R

The situation in which a gas stream flows through a bed of solids is found in many extractive metallurgy operations. Examples include blast furnace smelting, sintering and pellet firing. In such cases the resistance of the bed to fluid flow and heat transfer is of major significance to the operation of the process. This depends on the structure of the bed, which in turn is influenced by the manner in which the materials are charged to the bed. In this work, packed beds of hematite pellets of two different sizes were prepared in which the pellets were charged as a uniform mixture and in layers. The porosity, flow resistance and heat front velocity were measured and compared for the different bed configurations. For layered beds, the overall porosity and heat front velocity increased while the flow resistance decreased when compared with the values obtained for the uniform mixture. The size of the layers also had an effect on flow Properties.

Jan 1, 1991

By Sakurai F

Akita Zinc Refinery of Mitsubishi Metal Corporation (MMC) started operation in 1953 with a capacity of 560 tons of electrolytic zinc per month. Its capacity has been expanded gradually and reached 8,100 tons per month in 1973. However, present production level is about 6,500 tons per month due to the depressed zinc market. In 1963, newly developed sulphate roasting was incorporated for residue treatment. Since 1973, electric power from Ohnuma geothermal power station of MMC has been supplied in addition to hydroelectric power from Komata power station of MMC. At present, about 40% of power is supplied from our company's power station and the rest is from the power company. Recent customers' demands for zinc prod- ucts include various kinds of shape, weight and chemical composition of galvanizing zinc alloy. It is necessary for zinc producer not only to meet the requirements of customers but also to enhance the value of zinc product in order to expand the market of zinc.

Jan 1, 1987

By Kaleta S, McTavish LP, Turner RD

Primary production blasting at Hamers- ley Iron began with seven inch holes at Tom Price in 1966 and has developed since then to large multiple row shots of 381 mm holes at Tom Price and 311 mm at Paraburdoo. Up to 1.3 million tonnes are initiated in a single blast with the average around 300,000 tonnes. Development can be traced through Anfo, AlAnfo, slurries, various boosters, initiation and delay techniques, hole loading and daily operating practices. A standard practice could be developed for the two mines for normal pro- duction blasts; this would not apply to such common variations as low "paddy" shots, pre- splitting, tight corners necessitating single row drilling etc. Because of ground variation three or even four sizes of drill holes may well be economic- al for blasting, even though this would be off set by complications in operation, supervision, store stocking and maintenance, particularly in Drilling.

Jan 1, 1978

By Charles E. Glass

As partial implementation of the Surface Mining Control and Reclamation Act of 1977, the Office of Surface Mining (OSM), Department of Interior, has requested each state to inventory hazardous abandoned mining areas within their boundaries. Primary interest is in such areas .as unstable waste-banks, subsidence and slumping, contamination of water supplies, and preservation of overall aesthetic qualities through reclamation. In addition to the concern expressed for abandoned mining areas, the legislation requires a complete inspection of operating mines quarterly and a partial inspection monthly. In Arizona copper has been mined for over 100 years and coal and uranium mining promises to expand in future years. The OSM requirement for a waste inventory and frequent monitoring of Arizona's large, widely spaced mines places a severe demand on limited personnel and operating budgets. Remote sensing by satellite provides an attractive and effective approach to aid the inventory and monitoring requirements of the OSM legislation.

Jan 1, 1979

By Peck WH

For many years it was realised that the methods used for unloading concentrates at Port Pirie were inefficient and labour intensive, therefore, when a decision was reached to standardise the east-west rail link from Sydney to Perth, the opportunity was taken to consider entirely new schemes for the handling of concentrates at Broken Hill and Port Pirie. After considerable testing and investigation, it was decided to install a completely new concentrates handling plant incorporating a tippler at Port Pirieòto replace the previous long established methods of unloading and dis- tributing concentrates to the operating plant.and the shipping berths. To achieve this, wagons of concentrates from the various mines are marshalled in a set order at Broken Hill and conveyed to Port Pirie in 56-wagon trains. On arrival at Port Pirie, the wagons are checked and moved to a position where they come under the control of the automatic wagon marshalling equipment.

Jan 1, 1975

A major factor in the economic development of New South Wales has been the ready availability of coal for the major industrial and urban centres of Sydney, Newcastle and Wollongong. Historically, the presence of high quality coal near these areas has acted as a catalyst to urban and industrial growth. This easy access to low cost coal resources over the past 200 years has given rise to a commonly held belief that New South Wales contains vast coal resources sufficient to meet any foreseeable demand. However, a recent study undertaken by the Coal Resources Development Committee has found that New South Wales is likely to face a serious shortage of economically mineable coal in the future. Forecasts predict that demand for New South Wales coal will increase by about 40 per cent, and then remain at about that level for at least a further ten years. To meet such demands, the coal industry will require access to economic high quality coal resources.

Jan 1, 1995

By Suzann C. Ambrosio

Crude petroleum, the only commercially exploited mineral resource in Cameroon, continued to dominate developments in the mineral industry sector. International mining concerns have expressed interest in developing Cameroon's bauxite and iron and steel potentials. Domestically, the mineral industry focused on production of fertilisers for agricultural development, infrastructure construction, and hydrocarbon development, through the nearly self-sufficient production of fertilizer materials, cement, and crude oil. The mineral sector contributed 5.6% to the estimated 1981 gross domestic product (GDP) of $6.5 billion.2 Petroleum exports accounted for approximately 4.5% of the 1981 GDP and exceeded coffee and cocoa exports for the second consecutive year. The trade gap widened during the fiscal year ending on July 80, 1981, owing to a 21% increase in exports and a 25% increase in imports. Offsetting these balance-of-payments difficulties, typical of developing countries' early economic stages, were increases in foreign exchange reserves to $71 trillion by May 1983.

Jan 1, 1983

By C. D. Locker

COMMON salt is mentioned in the most ancient writings as an impor-tant article of diet. It is fairly certain that it was used by men and animals long before the dawn of civilization. Its presence in natural springs has often been the determining factor in colonization; wars have been fought for possession of salt deposits; trade routes have been estab-lished expressly for the purpose of traffic in salt. Naturally this led men into adventures and discoveries that altered history and advanced civilization. In the early days the uses for salt were few and the methods of manu-facture were crude and the purity low when compared to salt of the pres-ent day. Then the salt came largely from springs, shallow wells or the ocean, while today deep wells must be drilled to the natural brines or beds of rock -salt and spacious shafts sunk so that the ancient deposits may be made to yield their supply of stored mineral.

Jan 1, 1936