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By W. M. Armstrong, John A. H Lund

The paper describes an investigation of some of the tensile properties of single crystal vanadium, poly-crystalline vanadium and polycrystal-line tantalum, in the range of: W°C to -196°C. Techniques employed in the preparation and testing of specimens are discussed in detail. Some results of determinations of the temperature dependence of yield stress and ductility are given, and discussed in terms of the Cottrell-Bilby Theory of yielding. At subnormal temperatures, all the body-centred cubic transition metals in the Periodic Table exhibit; a) the "yield phenomenon" in tension, b) a strong temperature and strain rate dependence of yield stress, and c) a large decrease or complete loss of ductility. The yield phenomenon (existence of an upper and lower yield point) has been explained by Cottrell and Bilby ( 1) in terms of the dislocation-locking effect

Jan 1, 1961

By P. Cavanagh

Summary This paper discusses the fundamental principles which allow the development of a new method for studying the deformation and failure of metals in terms of 'internal microstrains'. Internal microstrains mechanical and magnetic properties are defined and their influence on of metals is outlined. A research programme at present in progress will determine whether magnetic measurements of internal microstrains give sufficiently accurate values for predicting the performance of metals under service conditions. These magnetic test techniques are also being used to detect the beginning of plastic deformation and to trace the development of deformation processes and failure. Results of the experimental work in each field will be published. Introduction Any attempts are being made to develop a complete theory embracing the mechanical behaviour of metals. In spite of the amount of experimental data available, the theoretical approach is rather difficult, since most of the mechanical properties of a metal are determined by deviations from the pure chemical composition or the perfect crystal. Both types of deviation are difficult to reproduce experimentally and to describe theoretically. In general, there are three main avenues of approach to the problem being followed today.

Jan 1, 1950

By J P. Bolduc, P. E. Pelletier

Preceded by brief general considerations such as the development of the mining industry in. the Province of Quebec, the choice of plant location, the types of problems studied etc., the paper gives a complete description of this new research and treatment center for metallic, non-metallic and asbestos ores. Facilities for carrying out operations in the three sections of the plant -the sampling section, the ore treatment section and the asbestos section -are fully discussed as well as laboratory facilities for (a) the preliminary testing of ores prior to pilot plant treatment and (b) the grading and testing of asbestos fibre. AT THE beginning of the century, the annual value of the mineral production of the Province of Quebec stood at the $2,500,000 level. Twenty-five years later, it was just under $24,000,000. In 1950, half a century later, it was slightly in excess of $200,000,000. But in 1959, in the span of only nine years, it

Jan 1, 1962

By T. Fekete, D. L. Flocks, R. T. Hart

The plugging effect of bacteria was investigated by injecting various concentrations of dead bacteria cells though sandstone cores. Pressure profiles along the cores were recorded periodically during the injection cycles. The plugging effect was analyzed using a plot of the ratio of reduced permeabilities to the initial permeability versus input volume. Results indicated that Tock permeability has little effect on plugging, but that the concentration of bacteria in the injection water has a significant effect on plugging characteristics. The pressure profile curves showed that bacteria penetrated several inches through the core but that the greater portion of the bacteria accumulated at the in-put end of the core.

Jan 1, 1960

By K. J. Palmer, D. A. Silva

"Evaluating resources and reserves requires the reliable modelling of geological domains and their grades. “Multiple point statistics” simulation is a relatively new geostatistical method to generate complex, high-resolution geological models by extracting high-order spatial relations from training images. A method based on combining multiple training images is developed to obtain the correct amount of large-scale continuity and short-scale variability. A calibration process matches the geological spatial variability between the final realizations and the drillhole dataset. A case study with data from the Red Dog mine, Alaska, United States, shows an appropriate reproduction of short-scale variability along boundaries between geological units.RÉSUMÉ L’évaluation des ressources et des réserves exige une modélisation fiable des domaines géologiques et de leur teneur. La simulation par « statistique multipoint » est une méthode géostatistique relativement nouvelle pour générer des modèles géologiques complexes à haute résolution par l’extraction de relations spatiales d’ordre supérieur à partir d’images d’entraînement. Une méthode basée sur la combinaison de multiples images d’entraînement est développée afin d’obtenir la bonne quantité de continuité à grande échelle et de variabilité à petite échelle. Un processus d’étalonnage fait correspondre la variabilité géologique spatiale entre les réalisations finales et l’ensemble des données de forage. Une étude de cas avec des données de la mine Red Dog, Alaska, États-Unis, montre une reproduction adéquate de la variabilité à petite échelle le long des limites entre les unités géologiques."

Jan 1, 2015

By Christina Graf

A synthesis of colloidal gold shell particles with a silica core is described. Small gold nanoclusters were attached to the functionalized surface of colloidal silica particles. Reductive growth and coalescence of these clusters lead to the formation of a closed gold layer. By variation of the thickness of this gold layer and the radius of the shell it is possible to adjust the plasmon resonance of the gold shell particles over the whole visible and infrared region of the spectrum. The optical properties of the particles made are in good agreement with theoretical calculations for coreshell particles. Due to their low polydispersity these gold shell particles form in solution large crystals with submicron lattice constants. It is also possible to produce hollow gold shells by dissolution of the silica core. A new method to coat the silica core gold shell particles with an additional outer silica shell is also presented. This allows due to a reduction in the Van-der-Waals forces to make more permanent dried crystals and facilitates functionalization of the particles for use in various photonic applications.

Oct 1, 2003

By M. Sukhram, S. A. Argyropoulos

"In the aluminum and steel processing industries there is a need for velocity sensors to measure the flow characteristics of liquid metal. This paper will present a sensor and an inverse heat transfer technique to determine the direction of velocity in flowing liquid aluminum. Experimental research work with the sensor involving liquid aluminum was conducted, using the Revolving Liquid Metal Tank at the University of Toronto, which rotates 50 kg of liquid aluminum with velocities up to 0.35 m/s. Experimental data for various magnitude of velocity demonstrate that the sensor records different thermal profiles under different fluid flow conditions. Using the transient temperature information and the inverse technique, the direction of velocity of the molten aluminum flow field can be inferred. INTRODUCTIONOur research at the University of Toronto has focused on developing invasive sensors to determine the velocity of high temperature liquid metals. High temperature in this setting is defined at VALUES (in excess of 660 °C. The discussion which will persist in this manuscript involves detecting the direction of flow in liquid aluminum using an inverse heat transfer technique. We first reported on the sensor which is used in this article in the following two publications (Sukhram and Argyropoulos, 2011a; Sukhram and Argyropoulos, 2011b). The motivation to perform this research is due to the lack of sensors available to characterize the conditions within a high temperature liquid metal reactor/vessel. A report conducted by The Minerals Metals and Materials Society (TMS Energy 2011) has suggested that the introduction of sensors into molten metal processing environments has the potential to increase process efficiency up to 15%. Such sensors will aid in the understanding of high temperature liquid metal processing operations with the goal to implement more efficient process design and practice."

Jan 1, 2012

By Floyd B. Bowen

Pumping methods are used, almost exclusively, to transport materials in the mining, beneficiation and chemical processing of phosphate rock in the Florida phosphate pebble field. Matrix pumping systems capable of pumping 15,000 g.p.m., transporting 15,000 long tons (dry) per hour, are now in use. They utilize 16-by 48 Yz -in. pumps, driven by 1.250-h.p. motors, discharging into pipelines 20 inches .in diameter .and sometimes several miles in length. As an average, it is necessary to pump 3 tons of matrix to the beneficiation plants, and to dispose of 2 tons of sand tailings and clay as waste, in order to produce 1 ton of shipping-grade rock. The washers and flotation plants, where the clay and phosphate and silica particles are separated, require the movement of large volumes of slurries with densities ranging from 2-3 per cent to 45 per cent solids, by weight. Extensive waste disposal systems require the pumping of dilute clay slurries in quantities of up to 50,000 g.p.m.,

Jan 1, 1963

By A. H. Lang

THE recent production of important quantities of high-grade muscovite at the Purdy mine, near Eau Claire, Ontario, bas brought that district into prominence and bas added another strategic mineral to the list of Canadian products. The discoveries are thirteen miles west of Mattawa and about two miles north of the Trans-Canada highway and the Canadian Pacific railway. HISTORY Clear mica of low power factor is in considerable demand in Canada and in the United States for war purposes such as radio and telephone condensers, aircraft spark-plugs, radio tubes, and transformers. Some muscovite (white mica) bas been produced in North Carolina and New Hampshire, but the United States trade bas depended largely on importations of muscovite from India and of phlogopite (amber mica) from Madagascar. For many years Canada bas been a substantial producer of phlogopite, but was unable to compete extensively in the United States with importations from abroad. Canadian production of muscovite bas been negligible as no important deposits were known. Ever since the construction of the Canadian Pacific railway, attempts have been made from time to time to mine the pegmatite dykes in and near the Eau Claire area, but, although some feldspar has been mined, no appreciable muscovite was produced. Lace in 1941, J. Purdy and H. MacDonald discovered a dyke containing large crystals of high-grade muscovite from which they are reported to have sold $700 worth of mica. They recorded claims 35974 and 35975 in December, 1941, and claim 36095 in May, 1942.

Jan 1, 1943

By F. P. Hassani, A. Hara, M. Momayez

To be competitive on the international market, the Canadian mining industry must reduce its costs, increase its productivity and maintain a high standard of safety. There is a great need today for improved methods that would allow the detection of geological structures in advance of mining to reduce dilution and the monitoring of underground structures to increase safety. This will facilitate planning for optimum exploitation of the mine and to increase production at lower costs. This paper discusses two examples of more efficient mine planning using new technologies such as Ground Probing Radar (GPR). In Kidd Creek mine, GPR technology was used at the 2500and 2600 levels to (1) monitor the stability of the sill pillar; (2) locate the presence of disseminated sulphide pockets in the sill pillar for extracting the mineral content; (3) monitor the stope backs and wall structures to evaluate the effect of on-time filling sequences; and (4)assess rockfill quality in terms of the presence of voids and fractures within the rockfilled areas. In the New Brunswick coal mine in Minto, GPR was used along with core log data to map and construct a 3D block of a section of the bench showing the relative position of different layers overlying the coal seam.

Jan 1, 1996

By E A. Mitchell

In the fall of 1961, Cominco dis-carded its long-established system of feeding the lead blast furnaces by narrow-gauge tram and V-cars, and installed an elevated monorail bucket system. This system automatically loads buckets of sinter, along with the correct proportion of coke, and delivers them to any of several designated furnaces. Direct labour usage has been reduced by nine men per day; improved coke proportioning has been achieved; and a major safety hazard has been eliminated. Introduction I N THE fall months of l 961. the system of feeding the lead blast furnaces at the Trail, B.C., smelter of The Consolidated Mining and Smelting Company of Canada Limited was altered from the tradition-al narrow-gauge railway and V-car method to one employing mono-rail carriers. The change was in keeping with a recent trend at Trail to replace narrow-gauge tramming with alternative methods of materials handling. In the case of the blast furnace feeding, the

Jan 1, 1963

By C. Kim

The integration of three-dimensional (3D) data with infrared thermography has received much attention for its potential use as input data for building energy simulations. Therefore, researchers have proposed methods to integrate 3D data with infrared thermography obtained by different sensors. These studies show the potential of the integration of 3D data and infrared thermography using various systems. However, these studies have ignored property aspects of infrared thermography, such as the low resolution of infrared thermography and external environmental influences. Thus, their proposed methods to integrate 3D data and infrared thermography are inadequate because these problems can affect the resulting building energy simulation. This research proposes a framework that integrates infrared thermography and 3D data while accounting for the resolution and shadow effect of infrared thermography. The proposed framework consists of three steps. In the resolution enhancement step, bi-cubic interpolation is proposed. In thermal data correction from the shadow effect, the shadow area is detected from the visible image, and then the shadow effect is removed from the registered infrared thermography. Finally, enhanced infrared thermography is mapped to the 3D data obtained by a laser scanner. The performance of the proposed framework was evaluated using test images obtained from a building in operation. The experimental results show that the proposed framework provides a 3D thermal model that is useful and accurate in simulating building energy. It is expected that the 3D thermal model can be used for accurate energy simulation of existing buildings. In addition, the proposed framework can be applied in defect detection for buildings. Furthermore, this novel approach enhances infrared thermography using visible images.

Aug 1, 2013

By J. A. Ressinger

"The purpose of this paper is to discuss some of the differences between various methods of excavating and loading as they relate to mining operations. The intent is not to provide ""pat"" answers, but instead to raise some questions and set forth some reasonable guidelines.Specifically, the paper deals with the differences and relative merits of power shovels versus rubber-tired front-end loaders - or, carrying this further, comparing what could be called ""stationary"" loading or excavating devices to ""mobile"" types."

Jan 1, 1972

By G. W. Harris, P. Mousset-Jones, J. Daemen

"To minimize ore dilution induced by blast movement in surface mines, it is necessary to quantify such movement. This will enable more accurate location of the grade boundaries beneath the surface of a blasted rock pile before excavation. A method has been developed and tested to accurately measure the direction and magnitude of subsurface blast movement. This technique uses a cesium vapour gradiometer and a real-time, differentially corrected GPS system to locate pre- and post-blast position of magnetically enhanced target objects placed within blastholes inside a bench. The procedure developed does not require the blasted rock to be disturbed, and the movement information is available within a sufficient time to allow for modification of the selective mining boundaries for each surveyed blast. It was found that the maximum depth of target detection was 18 m, with the overall accuracy being measured as ±1 m (horizontally) and ± 1.2 m (vertically). IntroductionOre dilution is a critical concern for many mining operations. In some instances, it may be the cause of considerable mineral loss. Where the mineralization is finely grained, sedimentary and disseminated in nature, and exhibits no clearly defined visual ore/waste boundary, there is a heightened possibility for ore grade dilution. In most modern open pit gold mines, it is economically desirable to minimize dilution in the production process through the practice of selective mining by defining pre-blast ore digging boundaries, called digging polygons, on the preblast bench area. The polygons’ positions are defined by sampling the production drill holes, with the resultant assay and survey data being used to estimate the areas of specified grade content within the bench. Once the ore is blasted in the bench, the pre-blast locations of these digging polygons are flagged as designated areas on the broken ore pile. The purpose is for the loader operator to be able to recognize which areas of blasted rock are to be sent to the appropriate processing facility or to the waste dump."

Jan 1, 2001

By Grant S. Diamond

THE BIBLIOGRAPHY on the use of static electricity in mineral beneficiation consists largely of patents. Some references are found in mineral textbooks, but very little data on flow-sheets of commercial installations are known to the writer. As a matter of fact there have been relatively few successful commercial applications of importance. Johnson prepared and published a Table showing the polarity and static field intensity requirements of many minerals. There have been reports of successful beneficiation of rutile, zir-con, coal, potassium chloride, and phosphate rock. Otherwise, the field of success has been very limited. This may be due to three reasons: first, the mining industry has been averse to dry processes, be-cause of dust nuisances in dry crushing; second, the electrostatic processes used in the past apparently developed no substantial economic advantages; and third, because flotation or other . methods have proven successful on many minerals, the industry has not felt the need for a radically different process. In the feldspar industry there was ?an attempt at electrostatic beneficiation about twenty years ago which was based on the use of fluoride fuming of the pegmatite head feed, in order to make the mineral reactive in a static field. This process was originally said to be successful, but was discontinued because of corrosion damage to machinery. Another effort by use of a chemical additive such as an or-ganic hydroxyl compound has also been attempted. Neither of these processes is known to be in use today.

Jan 1, 1957

By I. Spector

A SHORTAGE of cement in the Prairie Provinces, together with an aggressive policy on the part of the Saskatchewan Government in bringing new industries to the province, combined to create a favourable set of conditions for the establishment of Saskatchewan's first cement plant on the outskirts of Regina. Built by Saskatchewan Cement Corporation Limited, this single-kiln plant, tl1e latest addition to cement producers on the Prairies, began operations in the Fall of 1956. Location of the plant followed the trend of building cement manufacturing facilities in market areas rather than at raw material sources. In 1957, all assets of the Corporation were taken over by Inland Cement Company Limited and the plant and quarry now operate as Saskatchewan Cement Company, an Inland division. The Regina plant's production makes up approximately eleven per cent of the productive capacity of all plants in the Prairie Provinces. At present, two types of cement are manufactured -normal portland and sulphate resisting.

Jan 1, 1960

By C. H. Sleeman

"The Iron Ore Company of Canada constructed a beneficiation complex in Sept-Iles, Quebec, to concentrate and pelletize earthy red hematite iron ores from the Knob Lake area. The plants were scheduled for initial production during the first quarter of 1973.Many problems have been experienced to date. Difficulties in controlling the process, excessive mechanical failures, design deficiencies and manpower-staffing problems have caused an extended start-up. The problems are now essentially solved and, with the completion of some additional minor modifications, it is expected that the plants will be producing premium iron ore pellets at or near rated capacity within the next immediate period."

Jan 1, 1976

By M. N. Collison

"In 1960, with the opening of the Chisel Lake mine near Snow Lake, Manitoba, the Hudson Bay Mining and Smelting Co., Limited, commenced a new phase in their mining operation -that of bringing ore to Flin Flon over 100 miles of railroad.The schedule of operations required to accomplish this, together with an outline of some of the problems of handling ore at 40° and 50,0 below zero, are discussed. The facilities required to thaw and unload from twenty to fifty cars per working day are also described."

Jan 1, 1966

By G. A. Gross

DURING the past 5 years a large amount of money and effort has been expended in exploration of iron-formations and in testing their suitability for beneficiation. Beds of ferruginous material are numerous and widely distributed in the Precambrian rocks of Canada and practically all of the known iron ranges or belts have been examined to a limited degree at least in an effort to evaluate their potential as sources of iron ore. A number of favorable beds have been selected for mining on completion of surface sampling, diamond drilling, extensive metallurgical testing and economic studies, and many other ranges are being studied. There are still a great many iron-formations that have not been evaluated by modern concentration methods and their regional extent is not fully known. The iron-formations are easily located by airborne or ground magnetic surveys but the main task in finding a mineable ore-body of this type amounts to locating a bed sufficiently large for mining which consists of material that can be concentrated economically by modern beneficiating methods. The ease with which an iron-formation can be concentrated to give a marketable ore depends primarily

Jan 1, 1961

By G. E. Veins

This paper summarizes an investigation in which beneficiated ilmenite ore was smelted in a continuous, three-phase, 250 kv.a., open-top electric furnace. Minus %. inch ore was smelted, using the standard method. Fine ore, in the order of minus 14 mesh, was smelted in the briquetted form by the open bath method, and in the unagglomerated form by the cold dry-top method. The latter was shown to be superior. The data obtained .are discussed at some length. During the investigation, slag aver-aging 82.5 per cent Ti02 was produced over a period of 87 hours, the maximum being 85 per cent. Such slag should .be particularly attractive for the production of titanium tetrachloride, from which titaniurn metal is produced. The advantages of using paper-mill bark for producing a furnace charge of low bulk density, as required in cold dry-top smelting, were emphasized.

Jan 1, 1957