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By J. W. G. Hannon

FOLLOWING the experimental work of Denny, Robson, and Irwin, and the clinical investigation by Crombie and Blaisdell, an investigation of aluminium therapy was begun at Washington, Pa., which is situated in a very large industrial section of the State. Some of the men to be studied were from plants manufacturing silica brick, refractories used in steel and glass manufacturing, and semi-porcelain table-ware; others were workers in foundries, sand blasters, and men engaged in the quarrying of ganister rock. This group of workmen gave an opportunity to study the effects of aluminium on various types of silicosis which differed somewhat from that found in hard-rock miners. EXPOSURE In their occupations, the men studied were exposed to silica dust concentrations ranging from 17 to 97 per cent free silica. In the silica brick industries, the unfired product averages 96 per cent silica in the form of quartz, whereas the fired brick contains 50 to 62 per cent cristobalite plus 17 to 30 per cent tridymite, forms of silica that, on account of their higher solubility, are more toxic than quartz. The operational dust counts in the plants varied from 15 to 9,500 particles per c.c., and the median particle size from the aerial samples was 1.0 micron for the green product and 2.0 microns for the fired product. The length of exposure varied with the occupation as well as with the individual plant, but disabling silicosis could be produced in less than four years in certain exposures. The average time needed to produce radiological silicosis in those susceptible to this disease was eight years. Some of the men in our series of cases have been treated as long as fifteen years after exposure had ceased, and have improved under treatment.

Jan 1, 1944

By C. O. Swanson

Introduction It is thirty-odd years since I first entered the mining field by working underground at Anyox, which makes 1t clear that I can qualify as one of the older generation and claim the privilege of dealing in generalities and broad impressions. In this position I find it interesting to re~ view the salient changes that have taken place during the past quarter-century and indulge in some speculations concerning the future, with the hope that my comments may be of value to others engaged in the field of mining geology. As indicated by the title, the treatment is a perspective from a single viewpoint rather than an attempt to give a complete and impartial analysis. This plan, while deficient in some respects, has the advantage of being more specific than one based on .a. compilation of opinions. An additional advantage is brevity, which would be difficult to obtain on a subject of this scope if it were viewed from all angles. In conformity with the general plan, specific references to the literature have been avoided as much as possible, although a number of publications of general nature are listed at the end of the paper. This procedure is intended to give credit to the sources used without making them in any way responsible for the interpretation. The starting point for the discussion is the situation as it existed twenty-five years ago, when, as a recent graduate, I first had a fairly complete picture of it. However there is one impression of an earlier; stage that seems worth mentioning. In one of my first courses in geology the statement was made that some of the leading authorities of the previous generation, who guided geological thought at about the beginning of the century, were inclined to question the value of an association with mining. This attitude was no doubt exceptional, and certainly it was not adopted by the students who laid the groundwork for mining geology in North America. But its existence even in a limited circle is significant m showing how far the application of geology has advanced as the result of the investigations started during the first part of this century.

Jan 1, 1949

By A. Bhowmik

Uranium Refining is the process in which undesirable neutron absorbing elements such as Boron (B), Gadolinium (Gd), Cadmium (Cd), Europium (Eu), Samarium (Sm) and other heavy metals (Fe, Ni, Co, Ca, Mg etc.) are removed to make it nuclear pure. At present, Uranium refining is carried out by solvent extraction process by using organic based solvent e, g. TBP diluted with Kerosene. The above process generates lot of nitrate bearing liquid waste and degraded organic. In order to eliminate use of hazardous organic and ammonia for Uranium refining altogether, a new process has been developed. In the new process, Yellow Cake is dissolved in nitric acid and uranium peroxide hydrate is precipitated selectively from the solution leaving all the impurities in the solution by using commercial grade hydrogen peroxide at a pre-defined pH, U conc., temperature and stoichiometric quantity of hydrogen peroxide under mild agitation. The precipitate is filtered and washed with DM water to obtain nuclear pure product meeting purity standard as per ASTM C ? 753-99.The product is spray dried and calcined to obtain uranium oxide. The process eliminates use of organic, flammable, toxic chemicals, consumes less quantity of nitric acid and uses environfriendly chemical hydrogen peroxide. The process is simple and can be integrated in the mill. A patent application is entering national phase in several countries including CANADA and abstract/full paper is available in WIPO publication no: WO/2009/013759.

Aug 1, 2010

By W. Lin, Z. Z. Dong, C. L. Zhou, Y. C. Kuang

The inversion of rock mechanical properties based on well-logging data is a common method to drillbit selection in petroleum engineering, the basic principle of which is to use deep-well logging data and experimental regression model to calculate rock mechanical properties. The profile of rock mechanical properties can be established. According to the profile, the type of drillbit can be selected in different formations, which will improve the economic benefit of bit use indicators. Compressive strength of rock is one of the most important parameters. Conventional method to establish regression models of acoustic velocity and uniaxial compressive strength is on the basis of rock core sonic experiments and uniaxial compressive experiments. However, with the increase of deep drilling operation, triaxial compressive strength prediction model will play a more vital role in drillbit optimization selection in deep wells and improving ROP (Rate of Penetration). Triaxial compressive strength is an important parameter to evaluate the formation strength property. In this paper, to the sandstone commonly encountered in oil drilling, combined the rock mechanical experimental results with the changing porosity experimental results under confining pressure, a new interpretation model of triaxial compressive strength based on well logging data is proposed. Firstly, three types of sandstone samples are collected. Then measured components, uniaxial compressive strength, triaxial compressive strength and porosity. Experimental results show that: confining pressure has a significant influence on sandstone strength, with the increase of confining pressure, triaxial compressive strength increase; furthermore, the triaxial compressive strength of different porosity sandstones have different change rules when confining pressures changes; sandstone porosity decreases with the increase of confining pressure and it obeys logarithmic function. According to the results, regression models of sandstone, in-situ uniaxial compressive strength model and uniaxial compressive strength model under normal pressure are generated. Meanwhile, using well logging data in the acoustic velocity, density and gamma value can derive in-situ rock formations uniaxial compressive strength and in-situ porosity. Eventually, a new model established in this paper, containing in porosity, uniaxial compressive strength, lateral pressure and power exponent of regression, can predict triaxial compressive strength which will guide drillbit selection.

Jan 1, 2015

By P. Mišcevic, B. Kavur, I. Vrkljan, N. Štambuk Cvitanovic

It is known from earlier and recent research that mechanical properties of intact rock like uniaxial compressive strength (UCS), Young's modulus (E) and Poisson's ratio (?) are influenced by shape deviations of test specimens as deviations from the ideal cylinder. That impact can be significant at certain level of inaccuracy of specimen preparing, and it should be objectively evaluated and controlled in testing. The effects of intact specimens side straightness, ends flatness, ends parallelism and perpendicularity to the specimen axis, on UCS, E, and ?, measured in several actual ways during laboratory compression tests, were determined by previous research on 90 homogeneous specimens of limestone. In this paper, we subject these new experimental results to Response Surface Methodology (RSM) to model the mentioned dependence, to identify significant connections of variables and to evaluate the conclusions obtained directly from experimental phase. This study indicates how the responses of the model (outputs) – parameters UCS/E/??of limestone rock depend on factors (inputs) – parameters of specimen shape deviations like flatness R, parallelism P and perpendicularity O, assuming modern test machines with spherically seated upper platen. Starting from general RSM model with three factors (R, P, and O), we investigated the multiple linear regression models of specific mechanical property (UCS, E, and ?). Using the NCSS program ("NCSS 2004 and PASS 2005") in several steps, final models with very high coefficients of determination were developed for properties with the most evident effects of specimen shape deviations: nine models for strength UCS and UCS50 (equivalent UCS for specimen with 50 mm diameter), and three models for ?L (Poisson's ratio calculated from axial deformations measured on the entire specimen length). These statistical models with their response surfaces further strengthen and confirm the results and conclusions from the experimental phase. The critical values of R, P, and O are established using an additional statistical analysis to determine the lower and upper engineering limits. These findings set the basis for the new eligibility criteria for specimens of limestone (and similar rock with UCS about 100-150 MPa) in further testing of strength and deformability.

Jan 1, 2015

By Alex Matheson, Nick W. D. Massey, Peter T. Bobrowsky

Crowing pressures on aggregate resources include diminishing reserves, high transportation costs, sterilization and land use conflicts. In the absence of detailed resource knowledge for a particular region, aggregate resource potential maps provide the best "first approximation" regarding the surficial distribution of sand and gravel. The 1:50 000 scale Level Ill aggregate potential map integrates several important factors which influence the management of sand and gravel. Data used to generate this type of thematic map is readily available in most areas, fieldwork required is minimal, there is a logical quantitative evaluation of the data layers and integration is easily accomplished on a desktop PC-based platform. Also the aggregate potential map, with its focus on identifying areas of potential future aggregate exploitation as well as present inventory, provides a useful tool for the aggregate explorationist.

Jan 1, 2001

By F. H. Hueston, R. S. Barclay

"Depending on the application, zirconia, fused magnesia and graphite have been found to be the most suitable crucible materials for melting uranium metal and its alloys. Although graphite has been found to be satisfactory for uranium and uranium alloy castings with cross sections of 4 square inches or greater, ceramic-type molds are superior for small sections and those shaped castings which prohibit the economic use of machined graphite molds. Heating cycles, addition mechanisms and furnace conditions for melting are discussed."

Jan 1, 1967

By Ross D. Lawrence

"IntroductionOne of the methods used when applying the Market Approach to the valuation of a mineral exploration property is known as the Joint Venture Terms Method. The method is particularly useful for the valuation of early-stage exploration properties. Unfortunately, valuators are sometimes imprecise in distinguishing between joint ventures and other types of transactions.At VALMIN '94, Bob Appleyard1 proposed that, if one ignores the time value of money and the probability that the expenditure commitment would be completed, the formula to calculate the value ($V) of a property owned by Party B at the time of the deal would be:$V =$Ex (100-1%)/1% (Formula I)Where $V is the value of the property2Where $E is the expenditure commitment by Party A, andWhere 1% is the percentage property interest to be earned by party A.At PACRIM '99, Mike Lawrence and Graham Dewar3 referred to this method and suggested that there was an ambiguity in the formula proposed by Appleyard in 1994. Mike Lawrence referred to this problem again at VALMIN '014•Lawrence & Dewar suggested that the formulashould be:$V100% =($Ell%) x 100 (Formula 2)Where $V 100% is the value of the entire property,Where $E is the expenditure commitment by Party B, andWhere 1% is the percentage property interest to be earned by Party B.Subsequently, there has been considerable discussion in the AuslMM Bulletin5. In my view, this discussion has touched on a number of useful points, but generally has overlooked one essential element needed for an understanding of the correct application of the N Terms method. That essential element is to understand that there is a material difference between (1) entering into a joint venture arrangement and (2) the purchase of an interest in a property."

Jan 1, 2003

By W. E. Johnston

At last year's Annual Meeting a paper by Haultain and Johnston was presented entitled Is the Gold in Tellttrides Soluble in Cyanide? Since then the writer has continued the study of various phases of this problem. Samples and specimens of ore from some of the Kirkland Lake mines have been studied and non gold-bearing tellurides have been found in these that are not soluble in ordinary mill solutions. Samples of tailings, both old and recent, from this district have been examined with apparatus and methods that have proved very successful in detecting the presence of extremely minute quantities of tellurides. Tellurides, both base-metal and gold-bearing, have been discovered in these tailings, but only in such minute quantities that their presence would not affect the ordinary assay results. More free gold particles have been found in the tailings than gold-bearing tellurides. Much experimental work has been done on tellurides, concentrated from high-grade material and from ordinary run-of-mine ore. The gold-bearing tellurides behave very much as does gold itself. Finely divided particles are dissolved fairly rapidly, coarser particles more slowly. All the tellurides are soft and brittle and also have a high specific gravity, with the result that they are extremely finely divided in ordinary mill practice. The ordinary high-lime solution of Kirkland Lake practice is suitable for the dissolving of the gold tellurides. Oxygen is necessary, but apparently not more so than in dissolving gold. Some particles have been found that appear under the microscope to be ordinary metallic gold particles, but on heating they show a small telluride content. These appear to dissolve more slowly than gold. There is considerable variation in the ratio of tellurides to gold from different points in the mines. So far the writer has failed to find any connection between this ratio and the richness of the ore. Generally speaking, the base-metal tellurides predominate. Some of these contain gold but this may be due to a mixture of tellurides in the one particle.

Jan 1, 1933

By Micheal Mayhew

"This presentation will provide information and facts on the drilling and blasting within a frozen shaft using a full face methodology. The Author will briefly discuss the history of the sinking of a frozen shaft in Saskatchewan, the challenges faced, and the solutions delivered. The case study will include a discussion describing the series of events that led to the decision to adopt a full face blasting methodology. The case study will describe key elements such as the drilling pattern, hole size and depth, explosive products and blast vibration monitoring systems. INTRODUCTION During the shaft sinking process at a project in Saskatchewan, it was recommended that a drill & blast benching method be utilized. Following an evaluation of the site, the geological conditions proved amenable to a ground freezing system that would stabilize the rock formations and prevent inflows of water into the shaft (Table 1).The shaft sinking process required that the ground surrounding the proposed shaft be frozen by drilling several near vertical freeze holes radially at a specified distance from the edge of the proposed shaft excavation. This would allow for the circulation of a chilled brine solution down the freeze holes. The circulation is achieved by means of stainless steel pipes encased within each other to provide a delivery and return conduit for the brine (Figure 1). As a result of this periphery freezing, the ground within the shaft excavation is also predominately frozen.The finished internal diameter of the shaft was 5.5 meters with varying overall excavation diameters to facilitate different liner designs used for various rock formations. For the most part, the fully unsupported/unfinished excavated diameter of the shaft varied from 6.9 meters to 8.5 meters depending on the zone excavated. The challenge was that the proposed drill and blast excavation method posed a significant risk due to the potential to damage the freeze wall and pipes during blasting. The decision was made to commence the excavation through mechanical excavation (i.e. chip and cut) methods then change to a drill and blast method utilizing a split benching design. Through this process, the team encountered five main challenges: 1. Sub-horizontal geological structures and slips that affected blasting performance and sometimes resulted in a sloping surface to the top of the bench; 2. Confined working area for the crews and equipment due to a limited work area as a result of utilizing the split (half) bench drill and blast methodology; 3. Mechanical chipping and cutting of the one-meter buffer zone to the final shaft diameter; 4. Crews working on extremely slippery uneven frozen rock and ice surfaces, which affected safety and efficiency; 5. Establishing a blast vibration monitoring system to determine if the drilling and blasting of the full shaft excavation diameter were acceptable."

Jan 1, 2019

By A. Ignatieff

"THE WORLD'S coal resources represent the largest component of non-renewable energy resources. Coal is now regaining Its position following a temporary decline, particularly in North America during a period of about a quarter of a century. This period provided the opportunity to improve both surface and underground mechanization, thereby increasing the productivity and improving conditions for humans in the mines. Similarly, in preparation, improved cleaning of coal from various impurities including sulphur was achieved, to meet the more demanding requirements for coking coal. Progress was also made in combustion, particularly related to the reduction of pollution. Canada participated in most of these developments, despite the country's strong commitment of the use of hydrocarbons during this period. _Bearing in mind the vastness of this land (3.85 million sq. miles) by comparison with countries like U.S.A., U.S.S.R., and China, Canada's coal resources estimated to date are not large and they are scattered. The original evaluation of 1913 estimated the ""reserves"" from seams over one foot in thickness and a limiting depth of 4,000 ft at 1.2 trillion metric tons. D:. ~.R. MacKay, in his evaluation for the 1946 Royal Commission on the coal industry, known as the Carroll Commission, reduced the ""reserves"" to 99 billion short tons. The increased knowledge now available would indicate that the 1913 estimated was too liberal and the 1946 estimate too conservative but both were closer to a resource than to a reserve designation. Some adjustments of Dr. MacKay's estimates were made in 1970 by B.A. Latour of the Geological Survey of Canada and L.P. Chrismas of Energy, Mines and Resources Canada (EMR). In the last decade the Alberta Energy Resources Conservation Board has developed its own methods of evaluating coal resources and reserves. A methodical approach of exploration and evaluation was carried out by Saskatchewan jointly with the federal government of the lignite resources of Southern Saskatchewan. A similar joint program is in progress in Nova Scotia. Meanwhile, the industry itself carried on an extensive exploration program on the outcrops of promising projects in the Inner Foothills belt of Alberta and British Columbia in preparation for surface mining on a very large scale, with some development of hydraulic mines. All these activities have been reflected in the increase of the country's resources and reserves, which now fortunately are separately defined. In 1979 EMR issued Report E.R. 79/9(1>; the data were developed in 1978 and provided to the World Energy Conference Organization<2>. In 1980 the World Coal Study (Wocol), an international group that included Canada carried out a study which updated the W.E.C. data, indicating some reduction of the 1978 figures; quantities were reported in million metric tons of coal equivalent (C.E.)*(Jl."

Jan 1, 1985

By Pravin Mathur

"Praxair&apos;s CoJet® technology was introduced in 1997 to effectively inject chemical energy in electric arc furnaces. Coherent jets were invented as a revolutionary means of injecting oxygen and other gases into the EAF and into converters. Today, steel makers have widely accepted this concept in over 70 EAFs worldwide. Indeed, the whole industry has shifted to this new standard for chemical energy input in EAFs. CoJet® technology has also been implemented successfully in BOF converters.This paper will review the principles of coherent jets as applied to steelmaking. The key learnings garnered from several furnaces are also reviewed. In addition, while the CoJet® program has been widely accepted worldwide, based on steady feedback received from customers and the market place, several programs are underway in development and commercialization. These enhancements and new applications of CoJet® technology are also overviewed in the paper."

Jan 1, 2004

By R. W. Thompkins

In order to evaluate the impact of air quality control on mine design, a few examples are given of cases in wh.ich ventilation has affected the economics of the total design problem. Principles for the drainage of gas contaminants are shown, and the contamination control problems created by differential pressures in complicated booster fan installations are discussed. The paper also deals with the use of advanced mathematics for solving some of the ventilation problems likely to be encountered.

Jan 1, 1967

By P. J. Deveaux, M. J. Kreczmer

The Tartan Lake deposit 12 km northeast of Flin Flon, Manitoba, was discovered in March of 1984 during the investigation of a VLF anomaly. The discovery hole intersected 16.83 metres averaging 21 gm Au/tonne. Since then, 99 holes, over 21,000 metres, have been drilled outlining 419,491 tonnes grading 11.79 gm Au/tonne in a di stinct group of mineralized lenses referred to as the Main Zone. Three other mineralized zones are known on the property but no reserves have been allowed for these, the South , East and Base Line zones. The Main Zone consists of seven parallel, east-west striking, quartz lenses. The lenses dip steeply to the north and plunge steeply west to northwest. Lens number l strikes for 160m and extends vertically to the 90m level. Within th is lens there is a 60m interval of low grade materi al. Lens number 2 is located about 5-l0m within the foo twall of Lens number I. Near surface this lens stri kes for 40m, at 200m level the strike length increases to 200 m. To date the deepest mineralization on Lens 2 has been intersected at a vert ical depth of 527m. Five smaller lenses are located in the foo twall of Lens 2 , containing gold va lues similar to the two main lenses but erratically distributed. The South Zone, located 100m south of the Main Zone, strikes east-west fo r l00m above the 100m level. The East Zone, found 230m east of the Main Zone, strikes fo r 80m and may possibly be an ex tension of the South Zone. The Base Line Zone is located 275m south of the Main Zone. Sporadic, but very significant gold intersections have been obta ined1n all three zones. Gold-bearing quartz-ca rbonate tourmaline veins are generally confined to a silicous crystal tu ff hori zon. The crystal tuff exhi bits fi ve distinct types of alteration: silicification, sericitization, ca rbonati zation, chlorit ization and pyritization. Silicification has resulted in a perasive addition of silica and the generation of multiple quartz veins. Sericiti zation is restricted to the crystal tuff. All rock units are pervasively carbonatized . Ankerite is abundant in the quartz veins and within the shear zones, particul arly those located along the chilled margin of a nearby gabbro-diorite intrusion. Chloritization is widely spread th roughout the rock units, while pyritization fo rms a broad alteration halo associated with the orebody. Sulphide accesso ry minerals associated with the gold , whi ch fo r the most part appears to be free, are chalcopyrite and pyrite. Generally, the higher grade gold values are related to an increased content of sulphides in the qua rtz veins. The average sulphide content in the deposit is less than 5 %.

Jan 1, 1986

By Bhawani Singh, Mahendra Singh, N. K. C Samadhiya

"Inherently anisotropic rocks occur in abundance at many rock engineering project sites in Himalayan region. These rocks pose difficulty in analysis and design due to their direction dependent strength behaviour. Moreover the strength varies in a non-linear manner with confining pressure. Mohr- Coulomb strength criterion is widely used by geotechnical engineers for defining strength of rocks subjected to given confining pressure. However, the conventional Mohr-Coulomb (MC) criterion suffers from the limitation that the strength is treated to be linearly dependent on confining pressure. In the present article, the MC criterion has been modified by incorporating non-linear term while retaining the original parameters c and ?. The non-linearity with confining stress level has been imbibed through critical state concept (Barton, 1976). The criterion has been applied to a triaxial test data base comprising of more than 1140 triaxial tests conducted world-wide on anisotropic rocks. Statistical evaluation of the goodness of fit of the proposed criterion to the data-base has been carried out. Further the predictive capabilities have been evaluated by determining the error in estimation of triaxial strength if only few triaxial test data are available for determining the criterion parameters. The data base has also been back-analysed to assess the critical confining pressure for anisotropic rocks. Statistically the critical confining pressure, for the present criterion, may be taken nearly equal to 1.25?cmax, where ?cmax is the maximum value of the UCS out of all orientations of planes of anisotropy. It is concluded that reasonably good estimates of the anisotropic strength are possible through the proposed criterion.INTRODUCTIONMany rocks encountered in Himalayan region like shale, slate, schist and phyllite are inherently anisotropic and exhibit direction dependency in their strength behaviour. In addition, the strength of the rock also depends on the confining pressure and, the strength response is non-linear especially when the confining pressure may vary over large range. Conventionally, Mohr-Coulomb criterion is the most widely used criterion for rocks. However, the limitation of this criterion in its present form is that the strength is treated to be linearly dependent on the confining pressure. The present study attempts to address the following two main objectives: i) Include nonlinear response in the Mohr-Coulomb criterion while retaining parameters c and In their original form; and ii) consider anisotropic response of the rock for a given confining pressure. A nonlinear strength criterion, which uses shear strength parameters c and as per Mohr-Coulomb criterion, has been suggested based on critical state concept for rocks."

Jan 1, 2015

By K. R. Nichol

The author points out that corrosion works 24 hours a day, every day. It is an economic reality that the cost of corrosion is inevitable and that its cost should be incurred in the least expensive way. An economic evaluation technique to properly assess its relative impact is the Discounted Cash Flow Method. Various remedial and corrosion control measures are available and these, when coupled with a planned corrosion control program, help reduce the cost of corrosion.

Jan 1, 1973

By J. Paquin, P. Doiron, G. Proulx, P. Champoux

After nine years on a 36 hour schedule and two programs of creeping, the Alcoa Deschambault Potroom of faced the necessity of changing its organization for many reasons: the anodes butts were too small, the anode schedule was unbalanced, the iron content in the metal trends had increased, the metal tapping volume did not convene with crucible capacity and the liquid measurement task was delayed by tapping activities. A kaizen activity inspired the Potroom department to improve the organization. A team of 15 people including the process engineer, the process technician, team supervisors and Potroom operators developed a scenario, which would permit flexibility to creep pots if energy is available and an increase of added value production.This paper will describe the systematic approach, the communication method, the trials, the changes, and our success, along with the problems experienced by the team during the adaptation of Alcoa Deschambault Potroom organization over a 20 month period. Aluminium 2006 45th Annual Conference of Metallurgists ofCIM Montreal, Quebec, Canada Edited by

Jan 1, 2006

By K. W. Major

"This chapter outlines the organization of mine/ mill complexes in Canadian mining companies. Many factors unique to the Canadian mining industry will affect the design of the organization in the future: geographic location, the size and the type of orebody, etc. Mining companies cannot choose where new operations will be located, that is dictated by the location of the orebody. New mines are seldom started near established communities. Rather, the towns usually grow up near the mines. The remoteness of most Canadian mining operations has caused severe problems in attracting and/ or retaining all levels of employees. This means that training has a high priority within each operation.Another factor affecting mine/ mill organizations is the size of the operation. Larger operations generally require more departments and increased specialization to manage equipment and manpower effectively. Thus, for mine/mill complexes, organizational charts are less standardized than in other industries. It is often necessary to organize around the work force rather than develop a chart and then acquire the trained personnel to fill the diagrammed positions.The information presented in this chapter has been derived from the responses received from a survey of Canadian mining operations.Principles of OrganizationOrganization can be defined as deployment of personnel to accomplish definite goals. In the mining industry, the major goals are typically the projected number of tons and grade of ore mined on a daily, weekly, monthly and yearly basis. Organizing involves establishment of authority relationships with provisions for both vertical and horizontal co-ordination within the company structure. Vertical co-ordination is the delegation of responsibility and communication of goals and reporting of progress between the supervisor and subordinate. Horizontal co-ordination is communication between departments at positions of equal authority to determine methods of achieving predefined goals. The organization structure must reflect the objectives and plans of the company, and must clearly define areas of authority.Two criteria for effective organization are departmentalization and manpower planning."

Jan 1, 1989

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 &apos;internal microstrains&apos;. 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 N. Fukatsu

The recent development of galvanic cell-type hydrogen sensor for molten copper was outlined. The principle of the sensing mechanism, the fundamental structure of the sensor, and its performance as a process control device are discussed based on experimental work undertaken by the authors. Besides sensors based on usual perovskite-type proton conducting oxide, those using magnesium-doped alpha alumina, which was recently known as a proton conductor, were investigated and the results at the laboratory scale are reported. Considering the excellent sensitivity at high temperature and the stability to the disturbance from the attendant oxygen activity, magnesium-doped alpha alumina was regarded to be a superior material for the sensors used for such purposes.

Jan 1, 2007