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By Park Wright

THE fact that granite has been encountered by the drill by those in search of oil and gas in Kansas is becoming more and more a matter of interest, not only to the oil producer but to everyone directly and- indirectly connected with the oil business. It is, therefore, time that someone should offer an explanation for its presence and form a definite opinion based on all the data available in regard to the effect it will have on the future prospects of the area affected as probable oil- and gas-producing territory. At present there seems to be no consensus of opinion. To the writer's knowledge, only one attempt has been made to explain; by Erasmus Haworth, State Geologist of Kansas, in a paper entitled Bulletin, Number Two on Crystalline Rocks in Kansas. The purpose of the present paper is to offer a theory for the presence of the granite and to draw conclusions which will aid in determining the prospective oil and gas value of the area in question. In taking up this question it will be well to consider first the tests in which granite has been reported, with a general history of each. The accompanying map (Fig. 1) shows the location of all wells described. The first well in which granite was reported was that drilled just south of Zeandale in section 27, township 10 south, range 9 east, by a local company which had taken up a block of leases in that vicinity. At a depth of 958 ft. (291.99 m.) granite was encountered. Drilling was continued to a depth of 1,093 ft. (333 m.) in the same formation, at which depth the hole was abandoned. Another well was started 1 mile east of the first well and the same rock was found at a depth of 945 ft. (288 m.). Drilling was continued to a depth of 1,200 ft. (365.76 m.) with the bit in the sane formation. Samples of the drill cuttings have been examined and they are undoubtedly crushed granite. The next well in which granite was found was that drilled by DeLaat and Shepard, independent wildcat operators, in section 34, township 19 south,. range 7 east, near the town of Elmdale. Granite was struck at 1,707 ft. (520 m.) and the hole was abandoned in the same formation at 2,525 ft. (769 m.). Mr. DeLaat watched the drilling of this well very closely and he has described to me in some detail the formation immedi-

Jan 8, 1917

By Y. Poornachandra Rao, P. C. Sudhakar, L. Malakondaiah

NBV commissioned a 27.6 MVA furnace in the year 2005. This paper explains: a)Furnace design features b)Furnace process control, Direct slag granulation c)Continuous casting, Waste heat recovery, Sintering d) Gas cleaning plant, Protection of Environment. Keywords: Furnace Equipment, SiMn Production, Casting, Heat Recovery and Low hood

Jan 1, 2007

By M. E. Grimes

A method of predicting uranium extraction rate in underground bacterial leaching of as-blasted ore has been developed. The method is based on the hypothesis that extraction is directly proportional to the volume of a piece of ore that is penetrated by the leaching agent, and that each piece of ore, regardless of size, has been penetrated radially from the external surface to the same depth at a given leaching time. Consequently, given an initial size and assay distribution, extraction should be predictable for a given penetration. Two laboratory bacterial leaching tests under simulated stope leaching conditions were carried out for a periods of 89 and 96 weeks. On completion, the residual ore was screened and analyzed. The information so obtained was employed to provide an elapsed time base for the penetration model, from which predictions of future extraction were made. The finding of solubilized uranium trapped within apparently sol id ore pieces was unexpected. However, it is not recoverable except after crushing, and hence does not affect calculations of underground leaching .

Jan 1, 1974

By W. M. Kidd

INTRODUCTION Uranium mine inspection in Canada forms one element of the enforcement of the Atomic Energy Control Act; it is under this Act that all Canadian uranium mines and mills are licensed to operate. Inspection duties are carried out by a small core staff of federal government inspectors (working for the Atomic Energy Control Board (AECB)) largely supplemented by provincial mine inspectors working on behalf of the AECB. Unlike most resource extraction in Canada, uranium mining is under federal jurisdiction and consequently it was the AECB who decided in 1975 that changes in the Canadian uranium mining industry, particularly its expansion and the expanding role of the mine inspector in the limiting of exposures, warranted the offering of a special radiation protection training course. The Uranium Mine Inspector Training Course (UMITC) was first conducted in 1976 at the Elliot Lake Centre in Elliot Lake, Ontario. Subscription for the course was not limited to mine inspectors to enable union stewards, management personnel and provincial/federal labour inspectors to attend. This paper will present an outline of the course content, the format of its presentation and non-curriculum aspects of running a course of this type in uranium-producing community. The core lecturers for UMITC are drawn from the Radiation Protection and Uranium Mine Divisions of the AECB. In addition, guest lecturers are invited from universities and medical research centres together with industry professionals and government researchers. In all some twenty-four plus presentations are made over the first five days of lectures. The program topic areas, hazards, controls, measurements, record-keeping and health effects are preceded by an intensive half-day session on radiation fundamentals. TOPICS Hazards [Dust] A review of the dynamics of airborne particles including the effects of particle size, gravity and wake-turbulence on the behaviour of dust clouds. Associated topics are migrational aspects of dust particles and specific dust-generating mine operations. [Radiation] Canadian uranium mines are increasingly diverse in nature ranging from large scale low-grade underground operations in Elliot Lake to smaller high-grade open pits in Saskatchewan. Papers are presented on assessments of internal and external exposure, the metabolic pathways of ingested or inhaled radiation and the specifics of mine and mill hazards. Radiation hazards are further broken down into gamma surveys of uranium mines, radon daughter concentrations and problem areas. Controls The relationship between mining methods and the operating environment is critically important to ensuring safe working conditions. This refers to both the selection of machinery/devices, etc., and to engineering controls which are instituted to remedy problems created by new technology. UMITC examines a number of possible mining techniques, their criteria for selection and impact on the working environment. Control measures, ventilation practices and design, the need for continuous water misting and special open-pit precautions are presented. These lectures frequently conclude with suggestions for better operating guidelines for mine ventilation systems and the need for greater co-operation between the ventilation department and the underground crews. Measurements Uranium mining regulations stress the need for a high standard of exposure monitoring, statistical planning and record-keeping. [Statistics] Although many course participants are well versed in statistics, certain fundamentals are repeated and include, the concepts of mean, variance, standard deviation and standard deviation of the mean. Confidence levels, decision-making based on sample statistics and statistical records are also discussed. [Dust Measurement] Dust measurement is particularly critical in the mines where the high silica content of the ore body, such as those at Elliot Lake, results in the continuous generation of dust. Sampling practices, filtration, impaction, thermal impaction and electrostatic precipitation are explained together with the methods of counting samples to determine free silica. Konimetric and gravimetric techniques for dust sampling are compared and contrasted. [Radiation Measurements] Both collective and personal dosimetry systems are used in the Canadian uranium mining industry and lectures are presented on each. Techniques and possible sources of error are discussed for a variety of radon and radon daughter measurement methods - Lucas method, Tsivoglou and modified Tsivoglou, Kusnetz, Rolle. Instant working level meters and personal alpha dosimeters are explained in terms of calibration, maintenance, readout and estimation of accuracy. A lecture outlining dose estimation by means of bio-assay, whole-body counting and the use of TLD's concludes the topic. Record-Keeping An overview of the problems of changing limits,

Jan 1, 1981

By James Boyd

Scientists and engineers must concern themselves not only with technical problems, but with the socio-economic difficulties of our scciety. The author states that raw materials are basic to the economic process and that mineral raw materials occur naturally in nearly limitless quantities. He feels that the economic pocess will provide sufficient raw materials for man's needs, and discusses in some detail the world economic environment. As our society grows in complexity, it becomes more urgently incumbent upon scientists and engineers to bring their experiences to bear on the solution, not only of technical problems, but also on socio-economic difficulties. It is to this field that I have directed a large part of my energies. RAW MATERIALS BASIC TO THE ECONOMIC PROCESS There are certain premises, frequently overlooked, which bear emphasis. As economics concerns the production, distribution, and consumption of goods, so our whole society is based on raw materials. Without the basic extractive industries of agriculture and mining, there would be no economic problems with which to deal. This principle has been expressed as "All productivity is based on three factors: 1) natural resources, whose form, place, and condition are changed by the expenditure of 2) human energy (both muscular and mental), with the aid of 3) tools.77* It seems strange that such an obvious statement needs to be made. It is forgotten by all of us, however, at one time or another when we get involved in the complicated theories of economics dealing with the financial and fiscal policies of the various governments, in the financing of enterprises, in marketing, and in labor relations. Unless decisions in all of these fields are made with this, and the rest of the "Ten Pillars of Economic Wisdom," consciously in mind, the resultant policies are doomed to eventual failure, whether these are policies of individuals, companies, or governments. The economic process is basic to society. But economics and the social aspects of humanity are inevitably intertwined. If human needs are not provided for within the basic economic structure, conflicts arise to disrupt the most carefully laid social plans. Similarly, it is the failure of society to cope with basic economic prerequisites that leads to discord within the body politic and thus to eventual economic disaster. We who are engaged in the various aspects of the mineral industry, therefore, have a large part to play in society's future development. MINERAL RAW MATERIALS OCCUR NATURALLY IN NEARLY LIMITLESS QUANTITIES Throughout my career in and out of government, I have formed my decisions on two principles: 1) Fundamentally, all mineral raw materials exist within the earth's crust in quantities greatly exceeding man's needs; 2) Any problems of supply of these materials are primarily economic in nature. With respect to my first assumption, analyses by geochemists enable them to estimate the quantities in which each of the known elements exist in the earth's crust. One of the most cautious and famous suggests that the average copper content of the lithosphere to a depth of ten miles is about 55 ppm. If this is valid, then the lithosphere contains about 1.4 quadrillion (1.4 x 10 ") tons of copper metal — an unimaginable quantity. This is 8,500,000-fold that which has been consumed by man in his existence. To illustrate further, consider that the deepest copper mine in history went to about 9000 ft below the surface; the present copper mines of the world now average less than 1500 ft in depth. We can assume that in most continental land areas of the world it is technically feasible to mine to a depth of at least one mile. The land areas of the world to an average depth of one mile, then, contain 343 billion tons (343 x 10') of copper metal, or 2000 times that which has been extracted to date. I don't believe man will ever expend his energies to extract copper from rocks which contain only a few parts per million, but he knows that each element

Jan 1, 1968

By F. P. Schwarz, A. J. Erickson, S. M. Weber

The Mount Hope stockwork molybdenum deposit, Eureka County, Nevada, occurs In a small igneous cauldron complex 32 to 38 mybp in age. The deposit is characterized by alteration zones and mineralized shells symmetrically distributed around multiple intrusive. For samples from the 25000 meters of 1981-82 drilling, an appraisal of error in in-house sample preparation and in commercial assaying has been made. After splitting, drill core is crushed and reduced in volume (8: 1 at 10-mesh, 8: 1 at 70-mesh, 6: 1 at 200-mesh) to supply 25 grams of 200-mesh pulp for replicate analyses. A 0.5 g portion of the pulp 1s used for dissolution and atomic absorption analyses. Factors which initially generated unacceptable data variances have been minimized by planning, repeat analyses, introduction of standards, and routine monitoring. Assuming that error between replicate assays defines a Gaussian distribution with its average ideally equal to zero, precision (from preparation including core splitting and analysis of 8400 pairs of molybdenum samples) is on the order of ± 25%. The error distribution is not based. Accuracy is approximately 4% lower than absolute as determined by replicate assays of commercially prepared samples.

Jan 1, 1984

By O. D. Gonzalez

ThIS communication presents the results of a determination of the permeabilities of hydrogen and deuterium in a iron from 360° to 560°C. Recently Heu-mann and primas' have given values of the diffusivity and solubility in a iron of the two isotopes from which the permeability can be calculated. The work reported in the present communication, however, is a direct measurement of the rate of permeation of the isotopes through an identical iron specimen under the same conditions, so that systematic errors can be minimized in the calculation of the ratio of the permeabilities—the value which is usually of main importance in establishing limits for isotopic differences in diffusive processes. Experimentally the procedure used was the usual one: a steady-state flow of gas produced by a pressure difference across an iron membrane was observed as the pressure rise with time in a previously evacuated, calibrated volume connected to the outlet side of the membrane, while a constant pressure of gas was maintained on the opposite inlet side. The membrane was a cylindrical tube 9.38 cm long, 0.730 cm inside diam, 0.187 cm wall thickness, fabricated of 99.95 pct vacuum-melted National Research Corp. iron (less than 0.003 pct C). One end was sealed by a heliarc-welded iron (99.95 pctj lid of 0.147 cm thickness; the other end of the tube was welded to a 304 stainless-steel tube (0.318 cm ID and 0.318 cm wall) which connects to a vacuum system and to the calibrated volume including a dibutylphthalate manometer. The temperature of the iron membrane was maintained constant to ±0.l°C and was measured with an iron-constantan thermocouple which was calibrated against a standard Pt/Pt-Rh thermocouple: the temperature variation along the length of the membrane did not exceed ±0.5°C. Hydrogen was allowed to pass through the membrane assembly for 72 hr at 615°C before permeability measurements were begun. The system was tested at temperature before and after the experiments by a substitution of helium for hydrogen in the inlet side; under these conditions the pressure rise observed in the outlet side was negligible at all times. The gases used for the permeability measurements were 99.95 pct Matheson prepurified H2 and 99.7 pct D2 (0.3 pct HD) from the Isomet Corp. The gases were dried with liquid N2 before use. In Fig. 1 the logarithms of observed flows, jt, for a pressure difference of 73.4 cm Hg are plotted against T-1 Each point in Fig. 1 represents the slope determined by a least-square evaluation of a plot of the pressure in the outlet side of the membrane against time, including at least two separate sets of observations. Each point in the figure has an uncertainty of ±0.6 pct arising from the experimental uncertainty in the pressure and time measurements. The standard deviation of the observed pressures from the straight lines in all cases is less than the experimental precision of the measurements. The observed flow, jt, includes a small but not negligible flow through the stainless-steel connection.

Jan 1, 1968

By R Barritt, P Scott, K Albano

Successful closure of tailings storage facilities (TSFs) is an environmental issue faced globally by metalliferous mines. During the initial feasibility and design phase of the mine life importance is placed on the physical stability of above ground TSFs, largely driven by legislative requirements, whilst closure planning is often a secondary consideration. However, as the landform is further developed and constructed attention must be paid to regularly revisit the original closure plan and update it to achieve the best (sustainable) possible outcome for both the environment and stakeholders. A mine in northern Queensland is in the process of developing a closure strategy at their TSF. Appropriate closure measures for the TSF are required to mitigate the impact of any seepage emanating from the TSF on the groundwater and surface water receptors. O’Kane Consultants Pty Ltd (OKC) have provided the mine assistance with the development of a TSF cover system design in order to appropriately manage tailings during operations and to prepare for the facilities’ closure. OKC has collected data since 2007 from cover system field trials located on the TSF. To enhance engineering judgement in the design of future cover systems, calibration of soil-plant-atmosphere numerical models to field data (referred as ‘field response modelling’) were completed. Calibrated model inputs can be used to provide insight into long-term cover system performance as well as a tool for design of the final landform.Following a site investigation, materials characterisation and numerical modelling program various cover system alternatives were developed. Two of the preferred cover system alternatives referred to as Test Plot #1 (TP#1) and Test Plot #2 (TP#2) (Figure 1), were constructed at the site and instrumented. Monitoring instrumentation comprised several nests of in situ volumetric water content and thermal conductivity sensors to measure changes in water content, temperature and matric suction within the cover system materials and underlying tailings waste. Run-off collection buckets and a fully-automated meteorological station were also installed. CITATION:Barritt, R, Albano, K and Scott, P, 2016. Findings and conclusions following ‘long-term’ cover system monitoring – refinement of the conceptual design for tailings storage facility closure, in Proceedings Life-of-Mine 2016 Conference , pp 85–88 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By Oscar A. Glaeser

INDUSTRIAL relations in the United States Smelting Refining and Mining Company's Western operations covers the field of personnel and labor relations, and the principal aims are to render service to the employes of the Company and to its operating departments. Accident prevention Safety is a primary function. A safety engineer is employed at each operation. The wholehearted support of Company officials, staff, and the working force has been most successful in preventing accidents. Constant vigilance has been combined with a policy of building safety into all operating activities whether these are in the construction of a new facility, the developmnt of a mining system, or the direction of the working force. That this policy has produced results is attested to by the fact that the accident frequency rate at the Company's major mining operations in Utah has been reduced approximately 75 per cent in the ten-year period ending Dec. 31. 1946.

Jan 1, 1948

By D J. Corp

The Halmahera Contract of Work is a sixth generation contract held 82.5 per cent by Newcrest Mining Limited and 17.5 per cent by PT Aneka Tambang and takes in the Gosowong Project area. In 1991 Newcrest Mining Limited established a small exploration office in Jakarta and proceeded to seek exploration opportunities. The Halmahera area was identified as a substantial prospective ground position in a relatively unexplored area. In late-1991 Newcrest Mining Limited and PT Aneka Tambang agreed to explore in Halmahera. Initial field work commenced in July 1992. A vigorous ground reconnaissance programme led to the discovery of the Gosowong deposit a little over 12 months later in September 1993. In April 1997 the Contract of Work was approved covering much of the island of Halmahera. Between September 1997 and November 1998 activities were directed principally towards obtaining the necessary permits required to commence construction activities. Some particularly ambitious targets were set for achieving this outcome. An aggressive construction programme commenced in late-1998. Construction took place during a period of unseasonally high rainfall, which in itself presented additional challenges to the construction team. A key milestone for the project was achieved on 1 July 1999 when wet commissioning of the process plant commenced. Construction of the Gosowong Mine was achieved on time and within budget. A period of some six years elapsed from the initial discovery of the Gosowong deposit to the time of the first gold pour. Much of the permitting, construction and commissioning activity took place between September 1997 and July 1999. This coincided with a period of significant social, economic and political upheaval in Indonesia. During the construction period a high level of importance was placed on the structured recruitment and training of local people, as well as fostering appropriate community and local business development programmes in the communities nearby the project. Emphasis was also placed on environmental management with detailed long-term planning and progressive rehabilitation commencing during the construction phase. The permitting and subsequent development of the Gosowong Project has demonstrated that even during the difficult times, with commitment, it is possible for mining and exploration companies to conduct business in Indonesia.

Jan 1, 1999

By Tsunenori Shibata, Kazunori Jimbo, Kaoru Toya, Masafumi Matsumoto, Jinya Mitsui, Toshinori Tsuji

"The Toyama Line is under construction as a natural gas pipeline with a length of 102 km from Itoigawa City to Toyama City. A 2 km-long tunnel section of the pipeline that we are reporting here is being excavated in a mountain area away from an urban area. The geology under which the tunnel is constructed is collapsible fractured breccia slate and Holocene sandy soil. Other tunnels of the Hokuriku Expressway and Hokuriku Shinkansen are in service above the tunnel route. From the starting shaft on Toyama side, conventional tunneling was adopted to facilitate excavating the base rock layer and maintain enough distance from the Hokuriku Expressway tunnel. From the starting shaft on the Itoigawa side, TBM tunneling was adopted to cope with the unconsolidated soft ground for a 200 m-long section from the shaft. We will discuss the issues and countermeasures concerning the selection of a tunnel route and excavation methods, performance of both conventional and TBM tunneling, and underground connecting of these tunnels excavated by conventional (NATM) and TBM methods under a high groundwater pressure up to 1.2 MPa. INTRODUCTION AND BACKGROUND The International Petroleum Exploration Teiseki Co., Ltd. (INPEX) is constructing a high-pressure main pipeline network in the Toyama Prefecture area to promote the use and reliable supply of natural gas as shown in Figure 1. As part of the Toyama line project that has a total length of 102 km, A-1 construction, the nearest section to the tunneling starting point in Itoigawa City, where various tunnel excavation methods have been adopted to install the high-pressure pipeline 20 inches in diameter, a 2 km tunnel in the A-1 construction section discussed here is to be excavated by conventional and TBM methods in a mountain area. Based on environmental studies such as traffic jams due to frequent traffic of heavy vehicles disposing of soil, and the effects of dust, noise and vibration during construction, we selected the route to install the gas pipeline in a mountain area as shown in Figure 2, where the impact on the surrounding environment could be minimized."

Jan 1, 2016

By M. Yavuz

Underground mining method selection (UMMS) is one of the most important issues in mining engineering. Underground mining method should be primarily selected to make use of underground resources optimally. It is nearly impossible to change the mining method once selected by the reasons of rising costs and mining losses. Because of these reasons, UMMS process is extremely important in mine designs and economics. The strategy of underground mining method selection has been studied by different researchers in the literature. Boshkov and Wright (1973) proposed a classification system; Morrison (1976) suggested a selection chart; Laubscher (1981) proposed a selection methodology; Nicholas (1981) presented a classification system; Hartman (1987) developed a selection chart and Miller-Tait et al. (1995) modified the Nicholas? system and developed the UBC mining method selection process. In reality, UMMS is one of the important Multiple Attribute Decision Making (MADM) problems and mining engineers have always some difficulties in making the right decision in the multiple criteria environment. To make a right decision on UMMS, all known criteria related to the mining method selection should be analyzed and the problem solved according to suitable decision making techniques. A review of the literature reveals that decision making techniques have been used for UMMS applications. Kesimal and Bascetin (2002), Bitarafan and Ataei (2004), Bascetin et al. (2006), Alpay and Yavuz (2007), Karadogan et al. (2008) and Samimi Namin et al. (2008) used decision making techniques in UMMS applications. In this paper, two different MADM methods: Analytic Hierarchy Process (AHP) and Fuzzy Multiple Attribute Decision Making (FMADM) are applied to select the optimal underground mining method for a chromite mine and final solutions are then compared. THE AHP METHODOLOGY The AHP method developed by Saaty gives an opportunity to represent the interaction of multiple factors in complex unstructured situations (Triantaphyllou, 2000). The method is based on the pair-wise comparison of components with respect to attributes and alternatives. A pair-wise comparison matrix n×n is constructed, where n is the number of elements to be compared. The method is applied for the hierarchy problem structuring. The problem is divided in to three levels: problem statement, object identification to solve the problem and selection of evaluation criteria for each object. After the hierarchy structuring, the pair-wise comparison matrix is constructed for each level where a nominal discrete scale from 1 to 9 is used for the evaluation as shown in Table 1 (Saaty, 1980; Saaty, 2000). The next step is to find the relative priorities of criteria or alternatives implied by this comparison. The relative priorities are worked out using the theory of eigenvector. For example, if the pair comparison matrix is A, then, [Amax=××- [1] ] To calculate the eigenvalue ??max? and eigenvector w=(w1, w2,..., wn), weights can be estimated as relative priorities of criteria or alternatives. [ ] Since the comparison is based on the subjective evaluation, a consistency ratio is required to ensure the selection accuracy. The Consistency Index (CI) of the comparison matrix is computed as follows: [CImax--= [2] ] where ?max is maximal or principal eigenvalue, and n is the matrix size. The consistency Ratio (CR) is calculated as: [CR= [3 ] where ?RI? Random Consistency Index. Random consistency indices are given in Table 2. [ ] Table 2. The consistency indices of randomly generated reciprocal matrices As a general rule, a consistency ratio of ?0.10? or less is considered acceptable. In practice, however, consistency ratios exceeding ?0.10? occur frequently. THE FMADM METHODOLOGY The FMADM methods have been developed due to the lack of precision in assessing the relative importance of attributes and the

Jan 1, 2009

By Sir Robert Hadfield

Table 1 gives the composition of the specimens listed by the author. The details of test procedure and the results of the tests on mechanical, magnetic and electrical properties and cor-rodibility of the alloys are published in full in a paper by the same author, "Alloys of Iron and Manganese Containing Low Carbon," presented before the Iron and Steel Institute (of Great Britain) and published in full in their Proceedings for 1927, to which reference should be made. After reporting these tests the author gives the following discussion of results:] The studies here reported do not indicate that any of the series has really valuable or useful qualities for industrial applications, though the demands of industry are so varied that it is unsafe to prophesy that no special use will be found for a given material. The non-magnetic property of manganese steel is due to the association of Fe and Mn, but carbon has also an effect, enabling non-magnetic qualities to be obtained with a much lower percentage of Mn than would otherwise be the case; for example, 16 per cent. Mn is necessary for alloys practically free from carbon, while with 1 per cent. C nonmagnetic alloys may be obtained with as little as 7 per cent. Mn. Carbon, however, is the prime cause of the development of magnetic qualities by heat treatment. (Sec section 8 of the paper referred to above.) These Fe-Mn alloys show a resistance up to 87 microhms per c. c., but. as there are other alloys which have a resistance as high as 130 microhms per C. c., this does not provide any new feature of value. The most marked feature of the series studied is the brittleness in the range 3 to 10 per cent., with a maximum of brittleness at 7 per cent. Material with this percentage, while possessing quite appreciable hard-

Jan 1, 1927

By Hsun Hu, R. S. Cline

A detailed studj) of texture formation in 2 pet Al-Fe single crystals with initial orientations of approximately (111) [112], (112) [111], and (112) [111] was made by examining the textures developed on the surface and at various interior sections of the crystal after rolling to various amounts. Depending' upon the initial orientation of the crystal, the surface and interior textures may differ only in sharpness, or may differ essentially in orientation. The orientation of the (111) [112] crystal does not change upon rolling up to 70 pet, but after rolling more than 90 pet a distinct component of (001) (110] orientation is developed. The texture formed in the two (112) (1111 type crystals consists of (111) (1121 and (001) (1101 components. The latter, however, is largely confined to the surface layers. The textures formed on both sides of the crystal are identical, and the texture composition profile is approximately symmetrical with respect to the central section of the strip thickness. The formation of these texture components is analyzed. DURING the past seven or eight years, deformation and recrystallization textures in rolled Si-Fe single crystals have been extensively studied by various investigators.1-7 From these studies, much knowledge on texture formation in bee crystals of various initial orientations was obtained. However, these results also raised many questions, regarding particularly the correlation between deformation and recrystallization textures, as well as the deformation texture itself of some particular crystals. To take a (111) [112] type crystal as an example, it was shown by Dunn and Koh2, 3 that this orientation does not change during deformation by rolling. This finding is consistent with the conclusion reached by Barrett and Leven-son8 with respect to iron crystals that (111) [112] is one of the stable end orientations. However, different recrystallization textures were observed by Dunn and Koh3 in (111) [112] type crystals of different initial thickness, which widened differently during rolling even though their deformation textures were identical. Another interesting example, also from the results of Dunn and Koh2'3 is that of texture formation in a (112) [111] crystal. This crystal developed a two-component deformation texture of (111) [112] plus (001) [110]. Its recrystallization texture, however, was found to be predominantly (110) [001], which is related to the (111) [112] component by a simple [110] rotation. This crystal, therefore, behaved as if the other deformation texture component, (001) [110], were not present. There are also discrepancies among the results of different investigators, as well as numerous unexplained fine features of the deformation texture of crystals of various initial orientations. In order to have a better understanding of all of these points, a detailed study of deformation textures is greatly needed. One of the obvious things that has been completely overlooked in previous texture studies is the possible effect of surface texture. All past work on the texture of Si-Fe single crystals was conducted in a rather simple manner, i.e., the rolled crystals were etched to a very thin sheet; then their textures were examined by transmission X-ray techniques. For recrystallization texture studies, unless precautions are taken by etching off a sufficient amount of the surface layer before annealing, the texture developed in the interior may be affected by the surface layer, which may well have a different initial texture and which may have undergone recrystallization earlier than the interior of the specimen. Because of this effect, it is now planned to reexamine the texture of various rolled and annealed single crystals at the surface, and at various sections below the surface by using reflection techniques. In some cases, both surfaces of the rolled crystal will be examined. In one of Dunn's early papers,9 he noted that at an early stage of rolling the crystal seems to divide roughly through the middle to become a sample which in effect consists of two layers having some what different orientations. This effect has never been further explored. The investigation described in the present paper constitutes the beginning of a series of thorough investigations of texture formation in deformed bee single crystals designed to clear up some of the uncertainties which have been discussed. We have chosen a high-purity 2 pet Al-Fe alloy for this investigation. It is known that the allotropic transformation of iron is eliminated by alloying with approximately 1petAl. Such an alloy, being very similar to silicon ferrite, can be heated to the solidus temperature without phase transformation. One reason for choosing A1-Fe instead of Si-Fe for the present investigation is that we have been able to make single crystals of a vacuum-melted high-purity A1-Fe alloy by the strain-anneal method without much difficulty, but were not successful in doing so with a vacuum-melted high-purity Si-Fe alloy. For many research purposes,

Jan 1, 1962

By Klimpel. R. R.

Acknowledgments I am honored to be named as a recipient of the Antoine M. Gaudin Award, and I would like to briefly single out four groups who deserve a special thank-you relative to this award. The first group consists of Professor Kawatra, the many international support references that he gathered and the Gaudin Committee itself. I know such things don't come without considerable effort by many individuals, and I'm grateful for their support. The second group consists of the management of The Dow Chemical Company, the managements of various mining companies and, in recent years, the management of G. S. Technologies, all of whom supported me, financially and otherwise, in my grinding, flotation and other particle-processing work. Operations people are the most overworked and under recognized people in the world, whether they be in the mining or chemical industry. Obviously, without extensive industrial support, especially from operating personnel in the mining industry, almost nothing about the work contained in this lecture would have, or could have, happened. The third group consists of a number of coworkers who have played key roles in specifically implementing the new flotation-product portion of this lecture. Of these, Bob Hansen, Don Leonard, Basil Fee, Simon Isherwood, Fernando Cones and Marty Meulendyke deserve special recognition. They have not only been dedicated, but they have been great to work with. Also in this third group are many members of the international academic community, especially those at Penn State. Professor Leonard Austin must be singled out because he took me as a young mathematically oriented chemist and taught me to be an effective process-oriented engineer. Without this experience, I would not have had the over 30-year career as an engineer, which I have loved. In addition, Len planted the size-reduction-research virus in my blood, which I can't seem to get rid of. I also need to mention Professor Frank Aplan, whose obvious love of mineral processing and froth flotation helped to create my interest in flotation. Thus, for those of you who don't like my approach to flotation, it's all Frank's fault. The fourth, and certainly not the least, group to thank is my wife, Charlene, and our two sons, Richard and Steven. No one could have a more supportive family. In every sense of the word, my wife has been my partner from the beginningwe were married at the end of my freshman year in college. She has sacrificed much for me, and I will never really be able to express the depth of my gratitude for Charlene's encouragement, loyalty and support over the past 36 years. General comments on froth flotation The industrial process of froth flotation: Where is it going? I'm here to tell you loud and clear that froth flotation is alive, well, and growing. The inherent characteristics of high mineral throughput per unit of capital, low operating cost per unit of feed, high mineral specificity and high operating flexibility have guaranteed froth flotation an important past and a growing future. As with any evolving technology, there are always trends at the industrial level that are primarily driven by economics. The current trends include: •the movement towards larger and larger equipment, •more alternative equipment designs (e.g., the column cell),

Jan 1, 1996

By R. A. Pasternak, B. Evans

A dynamic technique for the determination of solubilities of gases in metals has been explored, using the N-Nb system as a test case. An initially clean sample, maintained at constant high temperature, is exposed to the gas at low pressure: the rate of sorp-tion and the corresponding change in sample resistance are measured continuously. A pronounced decrease in the slope of the resistance concentration curve is observed at the terminal solubility. The rate of gas uptake by the sample was determined in an ultrahigh-vacuum flow system equipped with a servo-control which maintains constant pressure in the sample chamber; the system and the technique have been described in detail elsewhere. 1,2 The sample was held at constant temperature during sorption by maintaining approximately constant power input into it; this results in constant temperature, since the emissivity of a metal is independent of moderate concentrations of dissolved gas. The simple electrical circuit used both for heating and for resistance measurement is shown in Fig. 1. The power input into the filament is where R is the filament resistance, RL is an adjustable resistance in series with the filament, and VT is the constant dc potential of the power source. If RL is set equal to R at the beginning of an absorption run, the power input becomes insensitive to subsequent resistance changes; for example, an increase of 20 pct in sample resistance is accompanied by a decrease in power input of less than 0.8 pct; i.e., the

Jan 1, 1967

By Lu Peiyan

A computation model of soil-pile (wall) interaction under lateral loading is presented in this paper. The model has been applied to some engineering projects, and the comparison between computation result and measured result shows good agreement, so the model is proved to be correct and practical.

Jan 1, 1991

By John F. Gartner

"New terrain maps provide information on the ground conditions in northern Ontario. This information has a relevance to mineral exploration because it assists the user in determining ground conditions prior to entering the area. The prospector, geologist, geophysicist and geochemist can then plan for the optimum use of exploration techniques best suited for theseground conditions.These terrain maps are the result of the Northern Ontario Engineering Geology Terrain Study-a program carried out by five consultants under contract to the Ontario Geological Survey of the Ministry of Natural Resources. The area mapped is 370,000 km2 and more than 100 basic data maps at a1:100,000 scale will be published.An unique terrain legend was derived to facilitate the mapping and it allows the derivation of specific user information. Examples of some of these uses are described. Introduction""Where did all the boulders come from Charlie?"", asked the student, as the prospector and his young assistant clambered through the bush. "" Why son, they were brought down here by the glacier"", the prospector replied. ""But where is the glacier now Charlie? "", persisted the young man. ""Gone back up north for more boulders son!""An old story, but one that illustrates the importance of overburden to the prospector. The use of overburden as a prospecting technique is not new. In fact, the principles have been known in the western world for at least 235 years (Shilts 1976). More recently, Dreimanis's classic work on boulder tracing (1957) and Lee's work (1971) emphasize the role of glacial geology in prospecting. In addition, papers by Smee and Sinha (1979), Averill (1978), Bereton (1978), and Gleeson and Hornbrook (1974) all describe the importance of drift in mineral exploration programs. The discovery of the copper deposit in the northern Ontario township of Currie (Thompson, 1979) is attributed in part to till prospecting methods. So the significance of the overburden is firmly established, both in the literature and in the minds of today's prospectors, geologists, geophysicists and geochemists."

Jan 1, 1981

By R. Kong, X. W. Zhang

"High pressure (up to 50 MPa) isotropic compression tests were performed on marble, gneiss and sandstone specimens, of which represents the typical rocks, to investigate isotropic compression deformation characterization at room temperature. Experimental data with respect to volume change in loading and unloading are presented. An apparent volume change inflection point (sensitive stress) was observed at a lower pressure range for porous sandstone, indicating that the elastic-plastic behaviour arising in the isotropic compression stage, but for tight crystalline rock, the sensitive stress is much higher, not probed prior to 50 MPa. The irrecoverable volumetric strain in the unloading can be seen for sandstone as well. The anisotropic deformation was discussed in terms of the axial and radial strain measurement. It was found that essential features of mechanical anisotropy are the irreversible in deformation range. The deformation feature in the isotropic compression tests is a very complex issue due to the factors concerning the stress history, unloading in sampling and in-situ stress. INTRODUCTIONThe isotropic or hydrostatic compression condition that stress is compressive and has the same magnitude for all direction, which is expressed as s1=s2=s3 in principal stress space. A yield locus of soils subjected to the isotropic and anisotropic compression was widely known, for instance Cam Clay model, which forms a closure cap model. However, the similar isotropic compression yield curves for rocks, especially for hard rock, was not established due to the geo-stress in the rock mass is much less than the socalled isotropic yield stress. And hence, the previous experimental studies on the hard rock have been made tend to on the stress-strain-strength relationship (Handin & Hager, 1957; Edmond & Paterson, 1972; Menéndez et al., 1996). Perhaps the yield curves related to an increasing in the hydrostatic pressure is not forced to construct for hard rocks, undoubtedly, the deformation data in this processing is valuable to assess the bulk module (Fabre & Gustkiewicz, 1997), anisotropy (Niandou et al., 1997), field stress (Hakala et al., 2007). Furthermore, many rocks store much elastic volume strain energy link to the hydrostatic pressure exerted, following a deviator stress applying, to drive the unstable brittle fracture for hard rock. Latter was studied to interpret the incentive of rock burst. However, volume change characteristic in the isotropic compression behaviour have been scarcely studied experimentally to our knowledge, less application related to the fracture in hard rock as well. The mechanical behaviour in the isotropic compression of hard rock is notably affected by the original structure anisotropy, stress history and stress condition before sampling, all of which need reasonably assess. It is also a useful understanding to study isotropic compression that elastic and plastic volume change in the isotropic loading and unloading, and the micro crack evolution throughout it."

Jan 1, 2015

By R. O. Kneisley

This U.S. Bureau of Mines report summarizes a study of large-scale strata response to longwall mining at a western U.S. coal mine. This study utilized surface and subsurface measurements, geologic mapping, in situ stress measurements, and pressure cell readings to characterize strata behavior. Preliminary analysis of surface subsidence and time-domain reflectometry (TDR) was used to determine a suggested main roof caving sequence. Coal ejected from the face apparently resulted from brittle failures that occurred because of lack of significant yield zone development. The combination of a strong coal with pronounced directional behavior, low overburden pressures, a good caving roof, and a high-production environment that minimized time-dependent loading apparently reduced yielding of the longwall face. The panel 1 headgate-entry design appears adequate; however, the abutment pillar and adjacent panel tailgate rib are highly stressed and may contribute to problems during second panel mining. The small chain pillar yielded after passage of the face, but the pillar width may be near maximum since evidence of a stressed core exists.

Jan 1, 2010