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By J. Drelich

We report structural forces measured for 10 nm silica particles deposited on alumina substrate and 5-80 nm alumina particles on mica using atomic force microscopy technique. For nanoparticles forming clusters, oscillation of structural forces was recorded with a periodicity that is close to the size of the nanoparticles used. Additionally, selected force-separation results indicate that the forces involved between the AFM probe and individual nanoparticles can be studied using the nanoparticle-coated substrates.

Jan 1, 2006

By D. H. Stonehouse

"ALTHOUGH final statistics are not yet available concerning Nova Scotia' s mineral production for 1958, it is estimated that the value will be slightly lower than that of 1957. In making this statement it is but fair to say that one year ago a reduction in mineral value was also forecast (for 1957 as compared with 1956) and final figures from the Dominion Bureau of Statistics ($68,058,743) indicated, instead, an increase of $2,000,000 over 1956. However, 1958 did bring problems to the industry which would indicate a drop in production value. The estimates figure for 1958 is $64,000,000. COAL Coal production came from 28 mines, 5 less than were operating since 1957. There were 5,269,896 tons of coal produced by 1,978,512 man-days' labour, for a tons per man-shift of 2.66 (0.05 higher than during 1957) or an increase of 1.9 per cent over the 1957 all-time high for this Province. This record has been established as a result of concentrated efforts to mechanize the coal mines of the Province, and it is hoped that it will be bettered during 1959. Collieries which showed some production for 1957 and none for 1958 were the McGregor at Stellarton, the Franklin at Sydney Mines, the MacLellan, the Rose bank No. 2 and the Rose bank No. 3 at Inverness."

Jan 1, 1959

By G. Plascencia, C. López, J. González, D. Jaramillo, M. A. Barrón

Air jet and molten matte interaction within a Peirce - Smith converter is analyzed during the first stages of blowing using Computational Fluid Dynamics (CFD), by means of the Large Eddy Simulation and Reynolds Stress turbulence models. Jet velocities ranging from 5 to 150 mis, which involve the bubbling and open jet regimes, were considered in 2 and in 3-D numerical simulations. As a result of the computer simulations, it was found that low velocities results in gas bubbling in the molten copper, whereas higher gas velocities results in well defined plumes. The consequence of such different behaviours results in an increment in the rate of refractory wear or in copper splashing respectively. The analysis of the results may lead to improve the design of the tuyeres currently used in copper converting. Bottom blowing of air is also explored in this work. Numerical results show a strong non-linear parabolic behaviour of the jet velocity on the average velocity of copper; which means that beyond certain jet velocity, the copper de-accelerates thus reducing its velocity. This may be due to the open nature of the jet, which prevents the momentum transfer from the injected gas to the molten copper.

Jan 1, 2007

By A. Torkian

Process water from production of concentrates in Meydook copper sulfide mine is transferred to the 8.3 million m3 tailings dam and a water retention pond after initial thickening. Elevated concentrations of heavy metals, sulfate, and TDS and decrease in pH as well as seepage into the aquifers have been the concern of the regulatory agencies since the start of activities. In this paper the results of a 6-month monitoring program from 4 wells are presented. The wells were located approximately 1.5 km from downstream of tailing dam (0.4 km from water retention pond) as well as upstream background well (2.28 km from water retention pond and 1.27 km from tailings dam). The objective was to study possible effect of accumulated tailings on the groundwater resources. Water levels in sampled wells were on average between 20 and 40 m. Results showed high levels of lead (5 ppb), copper (0.17-0.46 ppm) and selenium (73.1- 29.1 ppb). High levels of selenium and lead were partly due to natural geological settings of the area with high levels present in unaffected soils in the vicinity including water wells of villages upstream of mining operations. High copper levels were attributed to both mining operations as well as deposition from particulate air deposition onto the soil and transport to ground water by rain.

Aug 1, 2013

By L. López

Argentina reported about 40,000 tonnes of uranium (tU) as reasonably assured resources and inferred resources for the production cost category <130 US$/kgU in the OECD-NEA/IAEA classification scheme. These resources belong to the following projects: Sierra Pintada, Cerro Solo, Don Otto, Laguna Colorada, Laguna Salada, Meseta Central and Amarillo Grande. With three heavy water reactors in operation and an approximate installed capacity of 1.7 GWe, the current natural uranium requirements are about 220–250 tU per year. Based on various nuclear growth scenarios, it is estimated that by 2030 there will be a generation capacity of some 3,092 GWe for the reference case, with raw material needs of some 486 tU per year. Currently, there are no perspectives for local uranium production in the short term, and it is thought that uranium projects with identified resources must complete resource delineation and advance in technical pre-feasibility studies for the recovery of uranium. It is expected that Argentina continue meeting the uranium demand with imports in the next following years. In the Latin America region, both Brazil and Paraguay could be considered as potential uranium suppliers. In conclusion, despite the apparent growth prospects for the use of nuclear energy to generate electricity in Argentina, there are no immediate prospects for the provision of uranium oxide concentrates from domestic deposits for fuel fabrication. This has implications for supply and energy security.

Jan 1, 2020

By B. T. Lu

The corrosion and wear properties of a series of chrome white iron (CWI) castings were study using electrochemical and low-stress sliding abrasion tests. The results confirm that the corrosion resistance of these materials is largely dependant on the quantity of chromium in the matrix, while the wear resistance is mainly controlled by the volume fraction of chromium carbides. A pseudo-wear/corrosion map is developed to identify alloy compositions that may be suited for erosion/corrosion conditions.

Jan 1, 2005

By A. M. Cormie

Introduction The purpose of this paper is to give a brief, general outline of mining practices at Torbrit Silver mine. The geology of the mine is touched on as it is felt that a rough picture of the geology will result in a clearer understanding of the mining methods employed. The main part of the paper deals with mining methods and a section is included on haulage. Development practice is mentioned only briefly. Torbrit Silver Mines, Limited, a subsidiary of Mining Corporation of Canada, is located in the Alice Arm area of northern British Columbia. Access to the mine is by boat to the village of Alice Arm at the head of Alice arm, then truck road, following the course of Kitsault river for 18 miles in a northerly direction to the plant site. The main portal is a further two-thirds of a mile along the course of the river, at approximately the same elevation as the plant, 1,014 feet above sea level. Geology The ore occurs in a massive, irregular-shaped quartz-barite body replacing a folded area in a series of volcanic breccias, tuffs, and flow rocks locally referred to as &apos;green-stones&apos;. A series of parallel, nearly vertical, fine-grained basic dykes cut across the formation at right angles to the strike of the ore belt over a horizontal distance of 140 feet. The whole of the quartz-barite vein material, which ranges up to several hundred feet wide in places, carries silver values but commercial grade is confined to lenses and shoots where there have been more than usual concentrations of native silver and silver-bearing minerals. The ore-bearing structure plunges at approximately 25 degrees along an axis striking roughly N.65°W.

Jan 1, 1951

By Imre Gombköto, Barnabás Csoke

"Raw material management means not only mining and processing of primary raw materials like ores, but means also collecting and processing secondary sources of raw materials. Recycling is one of the most developing field of raw material management in Europe, and its solutions are derived from mineral processing roots and principals. Complexity and challenges of the field of recycling results innovative solutions of material processing- Since European Union identified 20 raw materials as critical (CRM) due to lack of primary sources within the border of the EU, recycling become more recognised as source of different raw materials. WEEE is the waste streams contains many of the critical elements and along them at least 15 different species of plastics of which recycling is delayed by a lack of effective separation technique. Most paper deals with separation methods based on different specific gravity, triboelectric charge or surface properties of plastic species. Plastics however have differences of thermal properties and thermoplastics, duroplasts and elastomers can be recognised. The experiments described in the paper aimed to determine thermo adhesive behaviour of plastic species often identified in WEEE streams for separation purposes. According to the results, some plastic types as PS, PP. PC or PVC and PET pairs are possible to easily separate from each other, however different additives are changing thermo adhesive properties of most of the plastics that makes industrial process difficult to develop. Along thermo adhesive behaviour, combination of physical interaction can be used to enhance separation selectivity.INTRODUCTIONPlastics has a relatively long term of history as a light, multi-functional material in construction, packaging, automotive industry and electric and electronic products. There are a numerous types of plastic species can be used for various applications therefore they amount are growing from year to year. This quantity however become part of the waste stream and while metal recycling has been done for decades due to its economic value - cheap plastic parts are less desirable as secondary products. In 2013 an annual 5% of plastic production growth has been estimated with a base data of 265 million tonnes at 2010 (Guiqing & Zhenming, 2013). Since landfill requirements are increasing while—especially in Europe where actual regulations are trying to deflect waste from landfills - landfill capacities are decreasing, costs are become more and more expensive, Applications like energy production based on plastics as a fuel or recycling are some of the options can be applied. Direct incineration of plastics are applied at many plants - in most cases where waste consist of dangerous substances are incinerated because plastics high calorific value helps correct average mixture composition enable operators reaching high enough temperature for combined power and heat generation while most of substances—like PAH, PCB or dioxins—are destroyed. Another path is using low temperature reductive cracking due to pyrolysis process, however the chance having higher concentrate of carcinogen substances in the products are higher since it applies around 400°C during the process."

Jan 1, 2016

By K. G. Chipman

The Geological Survey is the oldest map making department in the Canadian Government service, and when organized in 1842, one of the first principles to be recognized was the absolute necessity of having good maps. The primary purpose of the Survey has always been geology; but because a graphic representation by means of maps makes the written report .more readily intelligible; because the correlation of known geological facts is often difficult or nearly impossible unless they can be represented on a map; and, because the public demand information shown in this way, the Geological Survey must continue to supply maps; and the supplying of these maps must be considered as an essential part of the work of the Survey. It is a commonly recognized principle of pedagogics that an appeal to the eye is quicker than one to the ear; that children (and others) learn more quickly when a thing is presented to them through the eye rather than through the ear. The application of this principle to the work of the Geological Survey is that, to a large number of people, the message of a map is more quickly grasped, is more readily intelligible, and is in many ways of more interest and value than is the same information in a report. I do not mean that the maps are of more importance than the reports.

Jan 1, 1924

By Dong-Hyeun Koh, Yun-Soo Lee, Min-Seok Kim, Hyoung-Wook Kim

High strength AA7068 (Al - 7.88 wt.% Zn - 2.68 wt.% Mg - 2.07 wt.% Cu) aluminum alloy strip was successfully fabricated by horizontal-type twin roll casting. A simulation technique was used to obtain the range of casting conditions for fabricating strip without defects. The cast strip with thickness of about 5 mm was hot rolled, intermediate annealed, cold rolled to final thickness and subsequently annealed at various temperatures. Tensile properties of annealed and the aged specimens were evaluated at ambient temperature. Tensile strength and elongation of the annealed sheet are about 365 MPa and 28%, respectively. Also, the tensile and yield strength after the aging at paint baking condition (180 °C x 0.5 h) are 586 MPa and 551 MPa, respectively. Therefore, it is expected to show good formability prior to press or stamping and also provide high dent resistance after paint baking treatment.

Jan 1, 2015

By D. A. Barr

"The Galore Creek copper deposits are situated in the Stikine River district, 640 miles northwest of Vancouver, British Columbia. The deposits are primary cupriferous replacements localized in highly fractured zones lying in altered sedimentary, extrusive and intrusive rocks near the contacts of a potash-rich syenite porphyry complex which forms the core of a structural dome in Upper Triassic volcanic and sedimentary rocks. Ten deposits are distributed over an area of 3.5 by 2 miles and through an elevation range of 4,000 feet. The deposits share many of the characteristic features common to both the porphyry copper type of mineralization and pyrometasomatic deposits.Primary mineralization includes chalcopyrite and bornite, and is associated principally with pyrite and magnetite. The daminant alteration products are hydrothermal biotite and potash feldspar. Gypsum, anhydrite, garnet, chlorite and carbonate are commonly associated with sulphide minerals. Copper oxides, al-though present, are quantitatively of minor importance. The distribution of certain of the primary minerals reveals hypogene zoning characteristics.The results of stream sediment surveys, and airborne magnetic, ground magnetic and induced polarization surveys show important relationships to geologic structure and mineral deposits."

Jan 1, 1966

For the last few years, a new and innovative technique has been successfully used to determine refractory and castable thickness in various metallurgical vessels. The acousto ultrasonic-echo (AU-E) technique uses stress waves to detect metal penetration and delaminations within refractory linings. In addition, it is capable of measuring the thickness of refractory layers and build-up material. The inspection and measurements can be carried out while the furnace is in full operation. The present paper discusses the principles of the AU-E technique, and its advantages and limitations. A number of case studies are presented to demonstrate various capabilities of this new Non-Destructive Testing (NDT) technique.

Jan 1, 2005

By Y. Sugiyama, K. Kitazono, T. Miura, K. Matsuo

"Impact energy absorbing system for automotive is an important technology. Open-cell porous aluminum alloys were manufactured through Powder Bed Fusion (PBF) process. Compressive properties of the porous aluminum alloy depend on the cell structure as well as the porosity. The authors manufactured two ordered cell structures, truncated octahedron and rhombic dodecahedron, and one disordered cell structure, random Voronoi structure using a 3D-CAD software. Compression tests revealed the anisotropic deformation of the porous aluminum alloy with ordered cell structure. On the other hand, the porous aluminum alloy with disordered cell structure showed relatively isotropic and uniform deformation, which is suitable for energy absorbing applications. Therefore, controlling the disordered cell structure designed by Voronoi diagram enables to develop the advanced porous aluminum alloy having various mechanical properties.INTRODUCTIONAdditive manufacturing (AM) process enables to manufacture near net-shape mechanical parts. The AM technology is typically focused on titanium alloys due to their high specific strength and biocompatibility (Attar, 2014). Recently, aluminum alloy parts can be manufactured through selective laser melting method (Leary, 2016). Metal foams or porous metals are lightweight cellular materials having closed-or open-cell structures (Banhart, 2001). Aluminum foams are focused on as an energy absorbing material for transport industries (Baumeister, 1997). The purpose of the present study is to investigate the optimal cell structure of open-cell porous aluminum alloy manufactured through AM process. Most previous researches on the AM aluminum lattice structure has been considered ordered and periodic cell structures. On the other hand, classical aluminum foams manufactured through cast or powder metallurgical processes have disordered and heterogeneous cell structures (Körner, 2000). The authors use a concept of Voronoi diagram (Moukarzel, 1993) in order to manufacture various cell structures."

Jan 1, 2018

By Roderick C. McDonald

Great Bear lake, the fourth largest body of water on this continent, comprises an area of approximately 12,000 square miles, and is set astride the Arctic circle, with a large portion of it witnessing both the Arctic winter night, and the Arctic summer day with its midnight sun. The very name itself, Great Bear, suggests an Arctic region. The seasonal contrasts at Great Bear lake are very marked by the cold and darkness of winter, and the warmth and brightness of summer. Signs of winter such as low clouds, snow, sleet, fog, and night frosts, generally appear the latter part of August, while ice forming on bays during the last two weeks in September ends boat travel on the lake about September 30th.Early in June the ice leaves the river mouths, during the last ten days of the month it disappears from small bays, and at some time during the last two weeks of July the main body of the lake becomes navigable. In 1916, the ice disappeared earlier than usual, and the lake was navigable on July 5th. Great Bear river generally breaks up about June 1st, but, on account of ice cliffs and floes, it is not navigable with safety until early in July. Even then, the traveller is confronted with the Charles rapids, but these might be overcome by a wagon or motor road, such as the one from Fitzgerald to Fort Smith: However, in 1931, Mr. A. W. Boland, Fort Norman, N.W.T., carried with scow and motorboat practically all freight between Fort Norman and LaBine point and Hunter bay, at the east end of the lake. During July and August, two types of clothing are required, for, although the days are mainly ones of warm sunshine, the nights are cloudy and cold. In the winter season, fur clothing is used exclusively. Considerable timber, mainly white spruce, suitable for fuel and building purposes, borders the lake and extends eastward to the Coppermine river. North of the lake, no timber is found except in the river valleys, but with oil and coal possibilities near Fort Norman, the fuel situation might be solved.

Jan 1, 1932

By Jim Hazzard

A numerical investigation is presented to examine fluid flow in fractured rock slopes. In mining geomechanics, different numerical modelling approaches are used to estimate fluid pressures in open pit mines. The most common technique is the Equivalent Porous Medium (EPM) approach in which the fractured rock is assumed to behave as a porous continuum. Depending on the geometry and properties of the problem, this may not always be the best approach. The paper presents a parametric study to examine the effect of fracture spacing, fracture and matrix diffusivity and excavation rate on the fluid behaviour in rock slopes. Based on the model results, guidelines are provided as to when EPM models can be used and when different modelling approaches (e.g., discrete fracture flow) may be necessary.

Jun 1, 2012

By C R. Evans

Whole-rock and muscovite potassium-argon dates from selected low-grade metamorphic rocks of Precambrian age in the Canadian Rocky Mountains near Jasper, Alberta, were obtained to ascertain the age of the source terrain and the age of the metamorphism. Ten argillites gave whole-rock dates ranging from 270 to 485 million years, dates which are apparently inter-mediate between the age of the source material and that of the metamorphism. "Up-dating" increases with the degree of orientation of muscovite in the cleavage plane, and with the ratio of the muscovite in the cleavage plane to that in the plane of the bedding. Detrital muscovite from four arenaceous rocks gave dates ranging from 1,050 to 1,780 million years. "Updating" increases with decreasing grain size, so that, within the range investigated, the cube of the median diameter (¢) of the muscovite is apparently proportional to the radiometric date.

Jan 1, 1964

By C. R. Whittemore

PROGRESSIVE industrial organizations have recognized the importance of maintaining an adequate reference library of volumes covering all phases of their particular branch of industry, but it has been the experience of the writer that few engineers know how to use to the best advantage this store of extremely -valuable information which has been accumulated for their service. Nor does the average engineer appreciate the fact that it is only through the current technical literature that he can keep abreast of the rapidly developing fields of engineering. The present-day ramifications of the engineering field are of such wide scope that the human mind is not capable of storing away more than a small fraction of the information available on any particular topie; yet, from time ? to time, such information would prove invaluable. An engineer can know intimately only a small part of his own branch of engineering; but he cannot afford to neglect to take the fullest possible advantage of all that is already known in his own particular field. Technical information may be obtained by one or more of the following methods: (1) by enquiring of the individual who knows; (2) by performing the experimental investigations necessary to ascertain the facts; (3) by consulting the technical literature, where a record may be found of the work of others. This last method is the one we wish to examine. Our main consideration is the question of how to use the library, but first it is necessary to give some attention to the kind of enquiries one takes to the library, and to the nature of the sources of information available.

Jan 1, 1938

By L. A. Forsyth

"SINCE I received and accepted your invitation to present to this meeting a paper on A Canadian Integrated Coal and Steel Industry, I have given the subject a great deal of intensive study.Two conclusions have emerged from my considerations: first, that the subject should be dealt with by a person having a firm grasp of its technical aspects; and second, that it is a subject which requires expert analysis of the complicated problems it presents in pure economics.A third conclusion inevitably results from the two just mentioned -namely, that the mantle of the prophet which has been draped up-on my shoulders is too large for me to wear, because I am neither a practical nor a theoretical coal and steel man; and I am not an economist.With the warning that I have discovered, and am keenly conscious of, the inadequacy of my background for the task, I shall attempt to place before you those aspects of my subject which appear to high-light it from a layman's point of view.In the first place, in .order to avoid confusion as between my audience and myself, some definition of terms may be required.As I interpret it I am discussing -a coal and steel industry, using the last word in the generic and not the unit sense, self-sufficient in the provision of all its needs from within the geographical limits of Canada.Now, I start with the proposition that, in the very broadest aspects of such a concept, the Corporation of which I happen to be the executive head meets my definition as a combination of operations resulting in one fully integrated unit of a coal and steel industry."

Jan 1, 1952

By Gema Ribeiro Olivo

The hydrothermal Au-Pd deposits are hosted by the jacutinga in the Lake Superior-type iron-formation of the Itabira Group, Minas Supergroup. Jacutinga is a highly sheared, metamorphosed, hydrothermally altered iron-formation composed of hematite, magnetite, quartz, talc and phlogopite (Cauê) or muscovite (Conceição) and minor tourmaline, palladian gold, arsenopalladinite, mertierite II and palladeisite (hydrothermal) and native gold, native palladium Pd-Cu-oxides, and kaolinite (weathering products). The highest concentrations of Pd-Au occur in quartz and hematite veins parallel to the S1 foliation (Corpo Y, CorpoX, Aba Leste and Central orebodies, at Cauê and a single orebody at Conceição) or parallel to the S2 foliation (Aba Norte). The average ore grade is 30-40 g/t Au+Pd. The characteristics of the Au-Pd ore favor an epigenetic model for gold and palladium concentration in the iron-formation. During the D1 deformation and peak metamorphism, the oxiziding, acid and hot hydrothermal fluids transported Au and Pd preferentially as chloride complexes. The reaction of the fluid with the dolomitic carbonate (the probably protolith of the jacutinga) would have dissolved carbonate and K-feldspar to form muscovite or phlogopite and tourmaline, resulting in an increase in solution pH and a decrease of Cl concentration and subsequent deposition of gold and palladium minerals.

May 1, 2003

By D. D. Tannant, H. Ozturk

Thin spray-on liners are increasingly being used as rock support in underground mines. The adhesive strength between the liner and the rock surface is an important design parameter. Adhesion tests were conducted to assess the impact on adhesion of the presence of oil, water, and dust on a substrate, and the roughness and grain size of different substrates. Other factors such as curing time, loading rate, and liner thickness were also considered. Adhesion was measured using a pull test of a 33 mm diameter elevator bolt attached to an over-cored section of liner with strong epoxy. Most tests were performed using Tekflex liner material, although five other liner products were also tested. Adhesive strengths of about 2 MPa can be achieved with Tekflex under optimal conditions. Long-term creep tests showed that the adhesive strength could drop by at least 50% when the liner carries load for about a month. Where the rock surface is contaminated with dust or the rock is weak in tension, it may be difficult to reach adhesion strengths of 1 to 1.5 MPa. As the thickness of the liner increases, the adhesive strength to a substrate appears to decrease.

Jan 1, 2007