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By J. A. Jr. Carpenter

Expanding world economic prosperity, probable peaking of conventional petroleum production in the coming decades and environmental concerns require efforts to increase the efficiency of, and the development of alternatives to, petroleum-based fuels used in automotive transportation. In January 2002, the U.S. Department of Energy (USDOE) and the U.S. Council for Automotive Research (USCAR) of the "Big Three" traditionally-USA-based automakers, DaimlerChrysler, Ford and General Motors, formed the Freedom Cooperative Automotive Research (FreedomCAR) Partnership to fund high-risk, high-payoff research into advanced automotive technologies with the potential for eventually lowering the USA's nearly complete (95%) dependence on petroleum, 55% imported, for its transportation fuels. FreedomCAR replaced the Partnership for a New Generation of Vehicles (PNGV) which existed from 1993 to 2001. In January 2003, the energy-supply industry joined with the FreedomCAR Partnership forming the FreedomCAR and Fuel Initiative (FC&FI) to develop the technologies needed for the mass production of fuel-cell vehicles using hydrogen as fuel and the infrastructure needed to deliver the hydrogen to the consumer. The goal is to enable the automotive and energy-supply industries to make commercialization decisions in 2015 on large-scale introduction of such vehicles and on developing the infrastructure beginning in 2020. In addition to work on fuel cells and hydrogen infrastructure, the FC&FI conducts research on technologies with the potential for nearer-term energy efficiency and environmental benefits, such as new engine concepts, lightweight materials, and engine-electric hybrid propulsion systems. Lightweighting is seen as crucial for shorter and for longer term benefits because hybrid and fuel-cell powertrains are expected, at least in the early stages of adoption, to be heavier and more costly per unit of power than the standard internal-combustion, gasoline- or diesel-fueled powertrains they replace. Research and development (R&D) on casting of aluminum automotive components were major parts of the PNGV and R&D on casting of magnesium automotive components have been and are so under FreedomCAR. This presentation will review those efforts.

Jan 1, 2006

By Matthew Violot

Vale Canada?s Birchtree Mine, located in Thompson Manitoba, has been experiencing problems with hanging wall / footwall dilution, as well as sloughing off of adjacent stopes and temporary stope block backs. Birchtree Mine is interested in determining how time affects the stability of their open stope blocks. Many factors simultaneously influence open stope stability (rock mass quality, joint condition, stress condition). This makes it challenging to determine the influence of a single parameter such as exposure time or stand-up time. This study focuses on determining the effect of exposure time on open stope dilution and combines stress analysis and empirical based approaches.

Jun 1, 2012

By Raymond Dallaire

The Humphrey's spiral is a static gravity separation device which cannot be adjusted to match short-term variations that occur in the feed. Any disturbance in the feed grade, per cent solids or flow rate affects substantially the recovery and grade of concentrate. Such variations must be minimized in order to maintain the desired rate of production and quality of the product for which the installation has been designed. A study has been performed in which the foregoing assertions were quantified. The feed grade, per cent solids, flow rate and particle size were varied independently. Ore from Carol Lake, Nfld., was used throughout the experiments. This consisted of specular hematite and magnetite in a silica gangue.

Jan 1, 1978

By R. D. Brown

Higher employer costs and increased employee benefits will result from the current sweeping revisions of the un-employment insurance system now receiving consideration before Parliament. The new legislation, the Un-employment Insurance Act, 1971, will substantially increase the unemployment insurance costs of many employers through an increase in the level of employer contributions -generally, employer contributions will go to 1.4 times employee costs -as well as by extending coverage to many classes of employees now exempt. Under the new legislation, executives, technicians, teachers, institutional workers and others will be covered, and eligible for the higher benefits which it provides. For the first time, absence from work because of illness or accident may qualify individuals for unemployment insurance benefits.

Jan 1, 1971

By Hannu J. Häkkinen

Metal clusters exhibit unique size-dependent physical and chemical properties that differ from those of bulk materials or large particles. Here we discuss recent theoretical investigations of the catalytic properties of free and MgO-supported gold clusters. The catalytic activity of gold clusters depends sensitively on the environment, charge state, and chemical composition of the catalyst. Relativistic bonding effects stabilize large planar structures for gas-phase gold clusters, and non-compact ?quasiplanar? structures are present as important isomers also for surface-supported clusters. The hybridization of the atomic 5d and 6s states is significantly enhanced by the relativistic effects, and large spatial variations in the nature of the local electronic structure make the low-coordinated gold atoms preferable adsorption sites for oxygen molecules. The adsorbed oxygen molecules are activated to superoxo- and peroxo-states via charge-transfer from gold, and Eley-Rideal and Langmuir-Hinshelwood reactions with CO proceed via low-barrier formation of intermediates, which do not require O-O dissociation as precursors. This facilitates the low-temperature (below 300 K) activity of gold nanocatalysts in CO oxidation. Other gold nanostructures, such as mono-atomic gold nanowires, may also become important prototype systems in chemical sensing and nanocatalysis; here we show that they are active promoters of hydrogen dissociation.

Oct 1, 2003

By Hassan El-Shall, Ayman El-Midany, Patrick Zhang

Bench and pilot scale testing results suggest that significant improvement in dewatering characteristics of fine particles could be obtained by the addition of fibrous materials. Case studies involving flocculation and dewatering of wastes from phosphate, bauxite, and kaolin processing plants are presented in this paper. Several dewatering techniques were investigated, including sedimentation thickening, filtration, centrifugation, dewatering on screens, and seepage-induced dewatering and consolidation. Advantages and limitations of commercial application of some of the developed techniques arc discussed.

Jan 1, 2004

By J. A. Espinosa-Guillen, J. A. Lopez-Molina, S. García, J. A. Valencia-Quintanar

"The design and implementation of grouting treatments in rock masses are procedures that require continuous adjustment of parameters and criteria to optimize the results. In this proposal we describe a set of tools that enhance decision-making for this type of jobs particularly in dam projects. The methodology is focused on hydrogeological zoning of the site and its constant update combining engineer’s experience with artificial intelligence techniques to integrate the site knowledge; as well as the evaluation of grouting results for different scrutiny scales, with special attention on the relationship between water absorption and grout consumption. INTRODUCTIONSeveral methodologies for design, implementation and evaluation for grouting rock masses have been developed for the solution of specific problems and tested in diverse geological conditions. Each of these methodologies is focused on results evaluation for different scrutiny scales (Table 1) and is employed to assist decision-making before or during the grouting process.Some methods define specifications for grouting each stage of the borehole, making theoretical, semi empirical or experience-based considerations to define basic parameters as maximum pressure, maximum volume, grouting time, flow rate, etc. Ultimately each approach aim to optimize the injection process, adjusting volumes or the grouting time required to obtain satisfactory results, reducing risk of creating new flow paths or unnecessary grout travels, and enhancing the mixture properties to achieve adequate penetrability and long-term behaviour. Some of these criteria have been widely used in dam projects, for example the concept of Grouting Based on Facts to define the maximum pressure and volume (Ewert, 1997), the GIN method (Lombardi & Deere, 1993; El Tani, 2012), or the North American standards based on Apparent Lugeon measures (Naudts, 1995; Bruce 2011); on the other hand, there are relatively new criteria that have shown good results for dam grouting as the Aperture Control Method (Bonin et al., 2012; Carter et al., 2012) or the Real Time Grouting Control Method (Stille et al., 2012)."

Jan 1, 2015

By C. Vanvoren

"Since 1975, the Aluminium Pechiney Research Centre at Saint-Jean-de-Maurienne (LRF) has been concentrating its efforts on designing, testing and perfecting the Aluminium Pechiney point-fed prebaked reduction cell.In 1979, the AP18 cell (180 kA) was industrially launched with the construction and start-up of the F line in Saint-Jean. The following generation, the AP30 (300 kA), with prototypes started in 1981, was launched in 1986 on the Saint-Jean G line. Along with cell design, efficient process control systems were developed to pilot alumina feeding and bath composition. Together, these pots are currently producing 4.6 Mt of aluminum, i.e., 18% of the world’s overall yearly production.In 1989, the research centre faced a new challenge: to push the limits for the size of a reduction cell to further improve the profitability of Greenfield projects. This new generation development was also the opportunity for a significant redesign of the Aluminium Pechiney electrolysis information system.With a track record of ten years of semiindustrial operation with three prototypes, the AP50 technology is now ready for industrial implementation and enables a significant breakthrough to be made in terms of return on investment of a Greenfield smelter."

Jan 1, 2002

By E. S. Moore

"The Centre of the silver-producing section of the Gowganda area lies about 55 miles northwest of Cobalt, and the village of Gowganda is 71 miles by road from New Liskeard. The geological similarities of the Gowganda and Cobalt areas led prospectors westward from the rich Cobalt field, first to Elk Lake and then on to Gowganda, where mineralization was found in 1907. A year later many showings were found, and rich hand-picked ore was shipped. Most of the ore has come, however, from two mines, both of which are still operating; the Miller Lake-O'Brien, which was purchased by Siscoe Metals of Ontario Ltd. in 1945, and the Castle-Trethewey. The annual production of these two mines runs over one and one-half million ounces of silver and considerable cobalt. The total production of the camp has reached about 32,000,000 ounces of silver and a large amount of cobalt, the total not recorded.General GeologyThe general geology of Gowganda is in many respects much like that of Cobalt. There are areas of Keewatin basic and acid Javas mixed with tuffs and basic intrusions. These rocks are deformed and partly altered to schists, and have been intruded by some Haileyburian basic and ultra-basic rocks and by Algoman granite. These were followed by a large number of porphyritic Matachewan quartz diabase dykes. After a period of extensive erosion the Huronian sediments were deposited on a pene-planed surface over all the older rocks; these sediments include large quantities of conglomerate (partly tillite), quartzite, and greywacke. The Keweenawan rocks include the Nipissing quartz diabase sill, later quartz diabase dykes, and one long olivine diabase dyke, the latest Precambrian rock. The area has been extensively glaciated.Structural FeaturesThere has been little folding in the area since the Algoman batholiths were intruded, and the Huronian sediments lie nearly flat, with dips of 10, 15, or rarely 25 degrees. The Matachewan dykes show a remarkably uniform, nearly north strike, indicative of east-west tension when they were intruded. On the other hand, the dykes later than the sill strike nearly east, tangentially to the northeasterly and northwesterly strikes of the Miller Lake basin."

Jan 1, 1949

By F. Simon, A. Roth, M. F. Zaeh

Applying Friction Stir Welding in an industrial environment requires knowledge about the robustness of the welding process against imperfections in the joint line resulting from production deviations of the parts to be joined or from improper clamping devices. In this work the influence of gaps on the weld quality of friction stir welded butt joints of the aluminum alloy EN AW-5083-H111 is investigated in detail using the method Design of Experiments. As independent input variables, the rotation speed, the feed rate, the tilt angle, the lateral tool offset and the gap width were chosen. Tensile strength was selected as a measure for the joint quality. Moreover, the fundamental response variables of the FSW process, such as weld temperature, axial force and spindle torque, were recorded and integrated in the empirical process model derived by regression analysis. It was found that each response variable decreases with increasing gap width, whereas the largest impact was identified for the axial force and the temperature at the weld surface. In order to improve the joint strength for a given gap width, increasing the rotation speed and the tilt angle or lowering the feed rate, respectively, proved to be a suitable approach. However, interactions between the tilt angle and the rotation speed have to be considered.

Jan 1, 2014

By M. Mbonimpa

Field experimental cells were constructed in 2007 to assess the performance of different cover scenarios for the reclamation of the Parc 1 tailings disposal facility at the Westwood-Doyon Mine site (Abitibi, Quebec). Three configurations of cover with capillary barrier effects (CCBEs) with different thicknesses and material types for the moisture retention layer (MRL) were studied. MRL with 80 cm till, 40 cm till, and 40 cm clayey silt were used for cell nos. 2, 3, and 5, respectively. The capillary barrier layer (CBL) and drainage and protection layer (DPL) of the CCBE consisted of 30 cm gravel. A reference cell without cover was also constructed to compare the geochemical performance of the CCBEs. Due to an unexpected flooding in the leachate exit area of the cells in spring 2008, the cell instrumentation for hydrogeotechnical monitoring was postponed to spring 2009. Changes with time in volumetric water content, suction, soil oxygen concentration, and temperature were measured at different depths. This paper presents and discusses preliminary results obtained from spring 2009 to autumn 2010. In all cases, the degree of saturation Sr is lower in the CBL than in the MRL, indicating the presence of capillary barrier effects at the interface of these layers. Cell nos. 2 and 5 showed hydrogeotechnical behavior typical of an effective CCBE, with Sr maintained above 85% in the MRL and lower than 30?50% in the DPL and CBL. Based on the obtained results, and as expected, MRL thickness and the type of construction material used appear to affect the hydrogeotechnical behavior of the CCBE. Oxygen concentration profiles through the CCBEs were used to estimate the oxygen flux, and results indicate that cell nos. 2 and 3 performed better than cell no. 3. CCBE performance is currently being investigated using the geochemical monitoring data.

Aug 1, 2013

By T. H. Patching, D. F. Coates

The Sub-Committee on Rock Classification, Canadian Advisory Committee on Rock Mechanics, has evolved a classification of rocks which should prove useful in studies of rock mechanics. Considered in two stages -actual rock substance and rock mass -the five-point classification involves the geological name of the rock, the rock strength and rock deformation, and, in the second stage, the gross homogeneity of the rock mass and the formation continuity.

Jan 1, 1968

By He Zhexiang

The settlement properties of tailings modified by flocculants were investigated at the Shizhuyuan Mine, with the aims to screen for the most effective flocculants and the optimum dosage rates for tailings sedimentation. The settlement rate was used as the indicator of effective tailings sedimentation. Calcareousness and three polyacrylamides (F1, F2 and F3) were selected for settlement property evaluation. The results proved that sole use of calcareousness or any of the polyacrylamides had no apparent effect on the tailings sedimentation, while a remarkable acceleration of sedimentation could be observed with a combined addition of calcareousness and polyacrylamides, among which the addition of polyacrylamide F2 together with calcareousness is the most effective. The optimum dosage rate of F2 and calcareousness is 50g/t and 3kg/t respectively. The density of tailings slurry has an effect on sedimentation at the early settlement stage, with lower density generating quicker initial settlement.

May 1, 2007

By J. J. Quinn

Several mineral flotation plants utilize process water with high soluble salt content. The processing of semi-soluble minerals, the use of recycle streams, sea or well water give rise to this situation. It is unclear as to the overall effect on flotation response though there does seem to be evidence of bubble size reduction, increased froth stability and reduced reagent dosage. The present work aims to quantify the effects of salts present in process water on gas dispersion (bubble size and gas holdup) and froth properties. The salts examined were NaCI, CaCl2, Na2SO4, Na2S2O3 and Al2(SO4)3. Tests were conducted to determine the effects of salt type and concentration on gas holdup and bubble size distribution. The salts containing multivalent ions had a greater impact than the monovalent ions, in keeping with the literature. A relationship between gas holdup and ionic strength was established. The concentration of frother (methyl isobutyl carbinol, MIBC) giving equivalent gas holdup was determined. The effect of salt and frother combinations was also explored.Proposed mechanisms for coalescence inhibition in salt solutions are briefly reviewed in light of the current findings.

Jan 1, 2006

By S M. Roscoe

Relationships of Noranda sulphide deposits to volcanic rocks are reviewed and chemical variations within the volcanic sequence are described. The assemblages of minor elements in the pyrites and pyrrhotites of the Noranda and l\llatagami deposits are similar and are characterized by a high content of cobalt, tin and other elements. Isotopic compositions of lead, other geochronological data and stratigraphically disposed zonal distributions of sulphides and minor elements indicate that the deposits were formed prior to folding and metamorphism. Lead isotope data indicate that the Matagami deposits, and several others, were probably formed about 2.95 x 109 years ago and that the Noranda deposits may be about 50 million years younger. The volcanic sequence at Noranda is younger than the thick sequences bordering it on the east and on the west. The relationships are consistent with the hypothesis that these strata-bound sul1>hide de-posits are coeval with their associated volcanic rocks. T HE writer has been engaged in a metallogenic study of the region between Sault Ste. Marie and Chibougamau. An essential objective of this study is the classification of mineral deposits with regard to their composition, form, geological

Jan 1, 1965

By W. E. Cockfield

"The Last Chance claim is about 13 miles north of the village of Nicola and northeast of the city of Merritt; in the south-central part of British Columbia. It lies within Nicola mining division on the northern slope of Swakum mountain; near its summit. It may be reached by means of a branch road from the Kamloops-Merritt highway that leaves the highway at Nicola.The property was originally staked as a copper prospect by Oscar Schmidt in 1916. A number of cuts were driven and a test shipment of 22 tons of ore, averaging 4.6 per cent copper, was made from the surface showings. The property was then optioned to Granby Consolidated Mining, Smelting and Power Company, Limited, who did a small amount of drilling, after which the option was abandoned. The same year an option was secured by Northwestern Mines, Limited, of Spokane, and a SO-foot shaft was sunk. This option also was abandoned and after a number of years the property lapsed, but was re-staked in 1942 as a tungsten prospect along with other claims, and was drilled for the Metals Controller in 1943."

Jan 1, 1954

By Richard F. Lynch, Frank E. Goodwin

"The development of Galfan, a new generation 95% zinc-5% aluminum-mischmetal alloy coating for steel, offers opportunities for greater fabrication flexibility and upgraded corrosion performance in automotive applications. The formability of Galfan is equivalent to that of electrogalvanized steel, based on laboratory tests and automotive component fabrication. Corrosion resistance of Galfan exceeds that of hot dip and electrogalvanized, including performance in automotive industry tests. Automotive production applications for deep drawn and stamped components in France and Germany are based on the ability to meet dual performance requirements for upgraded formability and corrosion resistance. The first U.S. Galfan application was on 1985 model Ford cars and light trucks for transmission oil cooler lines which has now expanded into a number of power steering tubing uses. IntroductionContinuing requirements for improved vehicle performance coupled with the ever present need for reduced cost have spawned the development of a number of new coated steel products. Among this new generation of coated steels is Gaifan™, a 95070 zinc-Solo aluminum-mischmetal hot dip alloy coating. Galfan exhibits particular promise for automotive use based on broad fabrication advantages and upgraded product performance(I ),The unique characteristic of Galfan is the key combination of greatly improved formability with much longer corrosion life. Galfan provides significantly better formability than any other hot dip coating. Testing shows that formability is limited primarily by the steel substrate to which the Galfan coating is applied. Galfan exhibits excellent resistance to flaking and microcracking during commercial forming operations. The result is the elimination of unnoticed damage to the coating which would show up later as premature rusting on the finished product."

Jan 1, 1987

By M. B. McClenaghan

"Abstract - The Matheson area of northeastern Ontario is of great interest for mineral explo­ ration because of its geological similarities with the adjacent Timmins, Kirkland Lake and Larder Lake gold camps. Exploration in the area, however, is hampered by the presence of an extensive and thick cover of glacial sediments. For this reason, till geochemistry has be­ come an important exploration method. The Ontario Geological Survey&apos;s Black River -Matheson (BRiM) reconnaissance till sampling project, carried out between 1984 and 1988, was designed to aid exploration in the Matheson area by documenting the Quaternary stratigraphy and providing a database of till geochemistry. Till samples were collected by backhoe trenching of surface pits in areas of thin drift ( < 5 m) and by sonic overburden drilling in areas of thicker drift. This paper summarizes the results from the shallow till sampling component of the BRiM project.Two hundred and eighty-two surface samples were collected from Matheson Till, the youngest till sheet in the area, which was deposited during the Late Wisconsinan. For each sample, the non-magnetic heavy mineral (>3.3 S.G.) and fine (-250 mesh) till fractions were analyzed geochemically. In addition, visible gold grains were recovered by panning the heavy mineral fraction. Five areas that display multi-element anomalies in both till fractions warrant further investigation: (1) western Egan Township, overlying the Bradley Lake Syenite; (2) around and south of the Munro and Croesus mines, in Munro and Guibord townships; (3) central Garrison Township overlying the Garrison Stock; (4) south of Ore Car Lake in northern Thackeray Township; and (5) southeastern Harker Township. In these areas, Matheson Till has a local provenance and the bedrock sources for these anomalies are nearby in the up-ice (north­ northwest) direction. Due to the fine-grained nature of gold in bedrock deposits in the BRiM area, the small size of most gold grains recovered from till samples (<50 1-1m) and the variable distribution of gold in the heavy mineral concentrate and fine fractions, the fine fraction in addition to the more commonly used heavy mineral concentrate should be used for gold exploration.Surface till samples have been affected by weathering to a depth of s3 m. Weathered till is characterized by a very low carbonate content in the matrix fraction, the absence of sulfide grains in the heavy mineral concentrate and higher concentrations of copper, nickel and zinc in the fine fraction than in the heavy mineral concentrate. As a result of the weathered/ oxidized nature of the surface till samples, the fine fraction is a better sampling medium for base metal exploration."

Jan 1, 1992

By Nirmal Weerasekara

Mill liners serve the dual purpose of protecting the shell from wear and transferring the rotary motion of the mill to an effective grinding action. As the liners wear, the efficiency of energy transfer changes, so there is balance between liner profile for wear and for milling efficiency. A tool that can simultaneously predict the evolution of the liner profile and the associated change in milling efficiency should prove most useful in optimal liner design. This paper presents such an approach, based on measured 3D liner profile data informing 3D DEM simulations of charge motion and liner wear modelling.

Jan 1, 2012

By Zachary Mayer

Agenda ? Kidd Mine ? Background ? Problem & Opportunity ? Challenges associated to depth - Production Rates - Productive Work Time - Operational Delays - Transfer Levels - Mucking Time - Impact on Hoist ? LHD Automation ? Sandvik AutoMine Lite ? Expected Benefits Kidd Mine - Background ? Located in Northern Ontario, Canada ? Underground base metal mine operating since 1966 ? Total 148 Mt mined (2.31% Cu, 6.08% Zn, 75 gpt Ag) ? 2.35 Mt/Y from stopes as deep as 9500 ft (2.9km) below surface ? Mining method: blasthole open stoping ? Mine/Mill: 1263 employees and contractors ? 2012 National John T. Ryan Safety Award

Aug 1, 2013