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By W. B. Triplett, H. I. Aaronson, G. M. Andes

A detailed morphological study has been made of the pro-eutectoid TiCr, and the eutectoid reactions in a Ti-17.42 pct Cr alloy isothermally transformed at temperatures from 775° through 5561°C. The morphologies of proeute,ctoid TiCr2 were found to be subject to description by the Dube morphological classification system. Grain boundary allotriomo.lphs are the dominant plpoeutectoid morphology throughout the temperature range investigated. lntragranular plates, and especially Widmanstatten sideplates, form only in small numbers. This morphological pattern differs markedly from that of the proeutectoid a reaction in hypoeutectoid Ti-Cr alloys (AIME Trans., 1957, vol. 209, p. 1227; 1958, vol. 212, p. 624), in which plates form prolifically throughout wide ranges of temperature. The eutectoid reaction is nonlamellar in character at 675°C. An increasingly prominent lamellar component develops at lower temperatures. The proeutectoid TiCr 2 and the eutectoid transformations have been studied metallographically in a hypereutectoid titanium-chromium alloy. This investigation was undertaken with the immediate objective of comparing these transformations with their counterparts in hypoeutectoid titanium-chromium alloys, studies of which have been recently completed.1,2 It was also intended, however, to contribute to the general literature on transformations of these types. Especially in the proeutectoid case, this literature is still sufficiently sparse to make difficult the testing of generalizations on the mechanisms of these transformations. TiCr, is the only intermetallic compound in the titanium-chromium system.3-5 The TiCr2 phase field extends to a maximum temperature of 1350°C) and encompasses the approximate composition range of 62 to 68 pct Cr at lower temperatures.3'4 At temperatures below 1000°C, TiCr2 has a MgCu,-type fcc structure, with 24 atoms comprising a unit cell.6,7 Only fragmentary observations on the morphology of proeutectoid TiCr2 have been previously reported. An observation which is of considerable importance with respect to the results obtained during the present investigation was made, however, on anisother-mally transformed alloys with high chromium (48 to 70 pct Cr) contents.3"8 Despite the occurrence of extensive impingement, it is apparent that a substantial proportion of the proeutectoid TiCr, which precipitated in these alloys grew in the form of Widmanstatten plates. Several observations have been made on the eutectoid reaction in hypereutectoid alloys during investigations of the titanium-chromium phase di-

Jan 1, 1961

By Sun-Hee Cheong

This study sought to produce L(+)-calcium lactate using precipitated calcium carbonate as a starter culture composite of lactic acid bacteria in lactic acid fermentation. Specifically, precipitated calcium carbonate was synthesized by reacting calcium hydroxide with sodium carbonate in the previous study by the authors. Synthetic precipitated calcium carbonate was then used as the calcium source of lactic acid bacteria during the fermentation process. In general, precipitated calcium carbonate has low absorption rate in the human body. On the other hand, calcium lactate has high absorption rate; it is commonly used in food and drug industries as calcium additives in various foods such as cookies, beverages, bread, sauces, powdered milk, and fruit juice. Calcium lactate has two racemates, e.g., L(+)-lactate and D(-)-lactate. In particular, L(+)-lactate is known to be more soluble than D(-)-lactate and generally produced from lactose by homo-fermentative lactic acid bacteria such as Lactococcus spp., Lactobacillus plantarum, Lactobacillus casei, Lactobacillus curvatus, and Pediococcus spp. Thus, the characteristics of the pertinent lactic acid bacteria and optimal condition such as temperature, pH, precipitated calcium carbonate addition rate, and content of fermentation for increasing formation yield and purity were investigated. The findings suggested the possibility of manufacturing L(+)-calcium lactate using precipitated calcium carbonate as a calcium source with high value-added instead of commercial calcium lactate.

Jan 1, 2006

By P Moser, P Schimek, F Ouchterlony

This paper summarises the findings of 27 model-scale bench blasts in magnetic mortar, which were conducted from 2011 to 2014 at the blasting site of the Montanuniversitaet Leoben.The aim of the study was the investigation of the influence of blasthole delay times in small-scale bench blasts on the face characteristics and cracking damage created in the surrounding rock, which affects the fragmentation in subsequent rows.The test specimens or blocks, which were produced out of magnetite concrete, were roughly 1:100 in scale to normal bench blasts. The confinement of the testing blocks at the sides and back ensured the similarity to normal bench blasts with regard to the wave transmission into the surrounding rock. The specimen contained three or four rows with five blastholes each and were shot row by row, with virgin (undamaged) material in row 1 and increasingly damaged or preconditioned material in the following rows.The tested delay times varied between 0, 28, 73 and 140 µs, which corresponds to 0, 0.4, 1.0 and 2.0 ms/m of burden.The evaluation of the material properties showed that the use of magnetite concrete eliminated the inhomogeneous behaviour of rock, but some unexpected differences of the individual production cycles were still detected.The characteristics of the bench after each blast was evaluated along three horizontal lines out of a 3D model of the bench face. The tested delay time sequences of the virgin (first row) and single preconditioned blasts (second row) produced more overbreak for longer delays, while the third-row shots resulted in a smoothened surface independent of the chosen delay.The introduced damage after every blast was evaluated by an observation of irregularities on the newly blasted bench face. The visible cracks at the top of the testing blocks were documented and divided into several crack families according to their angle, length and origin. The remaining block was broken out of the blasting site after blasting, cut into several horizontal and vertical slices and dye penetrant spray was used to visualise the cracks created. Some of the detected crack families showed an influence of the delay time. The calculated mean crack density and mean crack intersection density showed that longer delays resulted in a higher degree of damage.The fragmentation results were well reproduced by the basic three-parameter Swebrec function. The observed improvement of fragmentation in the second- and third-row blasts was linked to the preconditioning of the burden for the following row while blasting the actual row. With the exception of the simultaneously initiated blastholes, the blasts showed coarser fragmentation for the shortest delays, while the longest delays generated the finest fragmentation.CITATION:Schimek, P, Ouchterlony, F and Moser, P, 2015. Influence of blasthole delay times on fragmentation as well as characteristics of and blast damage behind a remaining bench face through model-scale blasting, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 257–266 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By D J. Williams, G W. Wilson, S, A B. Tran

A comprehensive field program was implemented to evaluate the internal structure and hydrology of two full-scale waste rock piles. The excavation of waste rock dumps for in-pit disposal at the two mine sites provided an opportunity to characterise the in situ properties of the dumps given contrasting geologic and climatic settings. The internal structure and materials within the dumps were observed and sampled as the waste rock piles were being excavated and placed in the open pits for permanent closure. The field program was designed to fully characterise the structure and material properties of the waste rock. The alteration of the material by physical and chemical weathering was also observed. Samples were analysed for paste pH, water content, grain size distribution and geochemistry. In situ density and matric suction were also measured. Soil water characteristic curves and saturated hydraulic conductivity were measured for representative materials. These properties were used to predict seepage pathways through the waste rock and the resulting outflow geochemistry using the finite element model SEEP/W. The materials in the dump at Site 1 were predominantly fine-grained in texture and highly weathered. The presence of dipping beds with alternating coarse and fine materials was evident throughout the profile of the dump. The structure of the waste rock appears to have an impact on the hydrologic pathways within the waste rock pile. The material in the dump at Site 2 was found to be competent and resistant to particle size breakdown. The particles range in size from clay size to large boulders with the median particle size being approximately 125 mm in diameter. The coarse-grained texture of the waste rock resulted in a loosely packed arrangement of coarse particles with little matrix material infilling the pore spaces between the coarse-grained particles. Seepage modelling for Site 1 was completed to predict seepage paths based on observed structure and hydraulic properties measured in the laboratory. The modelling showed that materials with a fine grain size distribution become the dominant pathways for flow through the waste rock pile. The modelling also showed that layers with high silt and sand contents are subject to the highest flow rates. Finer grained clay rich layers have a low hydraulic conductivity and do not convey large volumes of water. Alternately, coarse gravel and cobble materials are unsaturated under values of matric suction that approach the residual water content of the material and do not transmit liquid water. The seepage modelling together with the results of the geochemical analysis show that the dominant particle size that receives the most fluid flow and flushing ranges from fine sand to silt, corresponding to materials with air entry values ranging between 5 kPa to 50 kPa.

Jan 1, 2003

By P. Hadzeriga

There are two places in the world where potash, trade name for potassium chloride, is economically recovered from naturally occurring brines by solar evaporation. One is at the Dead Sea and the other at Wendover, Utah. American Potash and Chemical at Trona, Calif. recovers potash from natural brines, but uses fuel to accomplish evaporation. Solar evaporation is always desirable, because of low costs, however artificial evaporation may be economical if a group of very valuable salts are recovered. This is the case for the American Potash operations at Trona. Solar evaporation is limited by low working temperatures, which in most areas of the world is between 18 and 45°C. In many cases the average working temperature is about 25°C. However, solar evaporation will have to accommodate itself to the highs and lows of each 24 hour period, and to the different average temperatures during the months of the year. Therefore, solar evaporation, although more economical than artificial evaporation, has a tem- perature limit which greatly reduces the chances of its application. The feasibility of solar evaporation as a means of recovery of values from a particular brine, may be evaluated by the use of phase diagrams showing the several components present. This paper is restricted to the five component system: C1-, SO4=, Na+, K+, Mg++, and H2O, which correspond to brines found at Wendover, Utah, the Great Salt Lake, and sea water bitterns. THE BONNEVILLE OPERATION AT WENDOVER, UTAH For more than 25 years Bonneville, Ltd., now a division of Standard Magnesium and Chemical Co. (recently acquired by Kaiser Aluminum and Chemical Corp.), has been recovering potassium chloride from the brines found in the desert area just east of Wendover, Utah. Solar evaporation of the brines is possible as a consequence of relatively low precipitations (year average: 4.8 in.), and of dry and hot summer months. The brine, collected by a series of approximately 67 mi. of ditches crossing the desert, is fed into solar evaporation ponds. Evaporation which takes place from around the middle of May to about the end of September, permits the crystallization of approximately 90% of the originally present NaCl on what is called the "General Pond Area". Further evaporation,

Jan 1, 1964

THE CHAIRMAN.-Thank you. Since the papers are rather closely related, I think rather than taking them one at a time we will entertain discussion on any of these problems at this time. W. A. REICH.*-We, of course, quite a while ago got the yellow light that Mr. Cole spoke of, and like everyone else immediately started to study silicon bronzes and brasses. We were interested in the silicon bronzes and brasses because we felt that in order to replace gun metal which makes up a large part of our use we needed something with an elastic limit at least equal to that of gun metal. That means at least 12,000 lb. per sq. in. This study was aimed only at tin conservation. Then we dropped the study of silicon bronzes because high purity copper which is needed in their manufacture became a scarce item. To make a long story short we have recommended to our designing engineers that they use 85-5-5-5 wherever possible because 85-5-5-5 we understand can be made entirely from scrap with little or no tin addition. 85-5-5-5 has a lower elastic limit than 88-8-4, so we felt that we would need another substitute material, a structural alloy with an elastic limit equal to that of 88-8-4, and we immediately turned to the manganese bronze type of alloy. The poor foundry properties of standard manganese bronzes were mentioned by Mr. Thieme and since we feel that high zinc content is largely responsible for this difficulty, our development is directed along the lines of uncovering a material with a lower zinc content and which gains its elastic strength from the addition of other alloying elements, such as, aluminum, manganese and iron. It must be possible to make this alloy entirely from scrap with no additions of scarce high purity material. I would appreciate an expression of opinion on how low we can go in zinc content with this type of alloy without seriously impairing the availability, and how high we can go in aluminum content without making use of aluminum restricted for that use. We assume that the maximum lead content must be placed at 1 ½ per cent to insure good availability and we feel that about I per cent of tin in the alloy would improve salt water corrosion resistance similar to the effect of tin in Admiralty Metal. Has anyone here had experience with the effect of tin and lead on the weldability of such an alloy? C. S. COLE.-What percentage of lead and tin? W. A. REICH.-About 1 per cent of lead and 1 per cent of tin. We are studying the weldability of the alloy but perhaps someone already has the answer. (Pause, no answer) The claim has been made that 1 per cent of lead can be added to certain silicon bronzes without impairing their properties. A silicon bronze with a low zinc content requires high purity copper in its manufacture but if say the 15 per cent zinc, 44 silicon balance copper alloy could be made, with a I per cent lead content, some quantity could be made from scrap. We do not know whether the aforementioned is

Jan 1, 1943

By David B. Reger

The value of carbon ratios in determining the boundaries of possible oil deposits appears to have passed the hypothetical stage. The theory that the ratio of fixed carbon in pure coals is an invariable index of incipient metamorphism in both surface and underground rocks and that it may be applied in defining the limits of petroleum, advanced by David White,' has been received with keen interest by many petroleum geologists. Detailed isocarb maps have been prepared of the Pennsylvanian area of North Texas and Eastern Oklahoma by M. L. Fuller.² A similar map of the coal-bearing area of West Virginia is given here. An isocarb3 is a line showing an equal fixed-carbon percentage, pure coal basis; the term has been proposed by David White to supersede a less expressive nomenclature. The term carbon ratio is applied to the pereentage of carbon in pure coal after water and ash have been eliminated. As a comparatively small number of analyses have been made on this basis, it is usually necessary to compute the ratio by dividing the fixed carbon of the proximate analysis by the sum of the fixed carbon and volatile matter of the same analysis. Many thousands of proximate analyses have been made by the West Virginia Geological Survey, covering nearly every county in which coal is found. Numerous others have been made by the U. S. Geological Survey and the U. S. Bureau of Mines, but as uniformity of results is best secured by adhering to one set of analyses, the tests of the West Virginia Survey have been cxclusively used.

Jan 1, 1921

By M. K. Jain, Z. T. Xu, M. Bruhis, V. Hegedekatte

"Strain rate and temperature dependent deformation conditions are present during elevated temperature forming of aluminum and other metallic materials. While many constitutive laws have been proposed to represent such deformation conditions, a closer investigation often reveals their limited applicability in terms of fit to the experimental data, and interpolation within and extrapolation outside of the range of experimental stress-strain curves. This is often because material-specific primary deformation mechanisms of temperature-dependent strain and strain rate hardening are poorly captured. In the present work, the Voce-Kocks constitutive model based on mechanics of dislocations storage and annihilation has been found to be suitable for many metallic materials. The model was modified to include the effect of temperature dependent shear modulus. The modified model is then employed to represent the experimental data obtained from uniaxial tensile tests on AA7075-O sheet at elevated temperatures and strain rates. Also, hot gas bulging tests were conducted to verify the applicability of this model. Further, finite element simulation of the hot gas bulge test was performed by incorporating the model as a user material subroutine. Good general agreement was observed between the experimental and FE model predicted results. Some sources of discrepancy in the prediction are also discussed.INTRODUCTION There has been much interest in light-weighting of automobiles from automotive related industries to reduce overall carbon footprint and increase energy efficiency of the vehicles. Aluminum alloys, and especially the medium-strength 5xxx and 6xxx series alloys, have been the primary focus in the last 3 decades to reach the above environmental goals (Huo, Hou, Zhang, & Zhang, 2016) whereas aerospace industry has traditionally focused on high strength 7xxx series aluminum (Al-Zn-Mg-Cu) alloys for structural components (Deng, Yin, & Huang, 2011). Recently, there has been much interest in high strength 7xxx series aluminum as a replacement for heavier steel automotive structural parts such as A-pillar, B-pillar, side impact beams etc. (Harrison & Luckey, 2014). This is both interesting and challenging since the above aluminum structural parts will need to not only meet impact safety standards but also possess sufficient formability for manufacturing such complex parts. Since the formability of high strength 7xxx series materials is quite poor at room temperature, much interest has focused on improving both formability and final part strength via high rate hot stamping, in-die quenching, and subsequent artificial ageing process steps (Kumar & Ross, 2016)."

Jan 1, 2018

By THOMAS G. FEAR

THE COAL DIVISION started its share of the annual meeting Monday morning with a study of coal classi fication. A. C. Fieldner was in the chair. The report of the tellers of the ballot for division chairman, stating that Thomas G. Fear had been elected to that office, was read by M. D. Cooper. Mr. Fear acknowledged the honor in a few words. In reviewing the history of the Coal Classification Committee the chairman pointed out that this was its third symposium, the last previous one having been held at the 1930 Annual Meeting. Throughout its work the com¬mittee has had the active cooperation of the Canadian workers who are interested in the subject which should result in a uniform scheme of classification in Canada and the United States. F. E. Lathe, of the National Research Council, Ottawa, abstracted the first two papers of the session entitled "Determination of the Alkali-Soluble Ulmins in Coal," by Edgar Stansfield and K. C. Gilbart, and "Moisture Determination for Coal Classification," by the same authors. The third paper "Condition of Water in Coals of Various Ranks"' was presented by its author, A. W. Gauger. Written discussions of these papers were presented by H. C. Porter and Gilbert H. Cady. In the oral discussion which followed, W. T. Thom, Jr., brought out the advisability of considering age as a factor in classification. Mr. Fieldner favored retaining bed moisture as a partial classification basis, stating that a review of many coal analyses revealed a remarkable consistency in this item in samples from a given mine particularly where the moisture content was not high. Mr. Porter pointed out that the structure and porosity of coal often have much to do with its moisture content and that these vary in different parts of a seam, particularly in anthracite. Mr. Gauger expressed doubt as to whether the Stansfield method gives the true moisture content of coal, which is needed for classification purposes.

Jan 1, 1932

By Stephen C. Tadolini

The U.S. Bureau of Mines conducted a laboratory investigation designed to evaluate the stress and deformation characteristics of fully grouted roof bolts subjected to various magnitudes of end loadings. The experiment and subsequent analysis were completed, utilizing axial deformation data obtained -ultrasonically from forty-one 4-ft, grade 40 roof bolts, with a total of 132 measurement locations along the lengths of the bolts. The ultrasonic measurement instrumentation used in this investigation allowed for elongation measurements without requiring extensive bolt modifications. The results indicate that approximately 39 pct o{ the applied end load dissipated within the first 3.4 in of the bolts. However, only 3 pct of the applied load was realized beyond 28 in of the grout column. Data are presented individually for every 6-in increment of bolt length, and analysis was performed using statistical, nonlinear equations developed for 5,000 and 8,000 lb loading conditions.

Jan 1, 1990

By S. B. Mishra

Ni-20Cr metallic coating was deposited on a Ni-based Superalloy (3Fe-19.5Cr¬0.3Ti-Balance Ni) by a shrouded plasma spray process; NiCrA1Y was used as a bond coat. Erosion studies were conducted on uncoated and plasma-spray coated superalloy specimens using an air-jet erosion test rig at a velocity of 40 m/s and impingement angles of 30° and 90°. The coating has been characterized for porosity, microhardness and microstructure and X-Ray Diffraction (XRD). An electron probe micro analyzer (EPMA) was used to obtain X-ray elemental mappings of the coating along the cross-section. Scanning electron microscope (SEM) with EDAX attachment was used to analyze the eroded surfaces.

Jan 1, 2005

By D. J. Bauer

A solvent-extraction system employing selective stripping of a pre loaded organic phase was investigated for recovering Sm203 from a light-group rare-earth mixture. The samarium concentrated in the organic phase, and a >99-pct-pure samarium oxide product was obtained at 76-pct recovery in a 20-stage operation using di(2-ethylhexyl) phosphoric acid (EHPA) as the organic phase. The stripping agent was a 1.5-pct hydrochloric acid solution containing 200 g NH4C1/1.

Jan 1, 1972

By Pollard D. M

The BHAS copper-lead matte leach process, developed in Port Pirie, South Australia, has been in operation on a commercial scale since 1984. This process is one of many developed in the past decade to recover copper via the hydrometallurgical route. In essence, the process involves a single stage agitative leach of 100% -75um matte in an acid chloride-sulphate lixiviant with gaseous oxygen as oxidant. The leach temperature is controlled at 85¦C to assist with reaction kinetics. After leaching, divalent copper is recovered from solution via a conventional solvent extraction/electrowinning circuit to yield cathode copper for sale The BHAS matte leach process has several unique characteristics cf. other commercial oxidative acid leach processes. These include i) the use of gaseous 02 as oxidant ii) H2SO4 addition as make up acid iii) Relatively low chloride ion addition (30 g/1) For this reason, extensive work was carried out into the optimization of leaching by Meadows (1985). Variables investigated included ò Oxygen flow-rate ò Agitation intensity ò Leach temperature ò Free acidity ò Chloride ion concentration ò Matte particle size The current work was conducted to determine the effect of cooling rate, and hence mineralogy, on the leaching characteristics.

Jan 1, 1989

By John T. Galey

Production of crude oil for 1940 in southwestern Pennsylvania was off nearly 70,000 bbl., largely as a result of the great number oi abandonments, together with the lack of extension of the Washington and Green County pools. Oil wells completed numbered 51, which is 26 more than last year, but the total initial production of 259 bbl. is only 18 bbl. greater than in 1939. There was an increase of 72 over last year for a total of 209f gas wells. However, 68 7 dry holes were drilled, which is 40 more than a year ago. Thus, 328f wells were drilled during the year, and rigs are erected or drilling is progressing on 59 t more. Shallow Development Oil.—Butler County led in number of oil wells completed, with a total of 27 for an initial production of only 69 bbl. Washington County, with 12 new oil wells, one of which made 40 bbl. from the Fifth sand in S. Franklin township, has 95 bbl., while in Allegheny County 9 wells gave an initial of 86 bbl. for the highest Per well average in the area. This initial was given a considerable boost by one 35-bbl and another 2;-bbl. well in West Deer township, where the Fourth sand produced at 1840 feet. Greene County had only one oil well completed during 1940, and Washington County had 12. The subnormal totals for these counties may be explained by the higher cost of completions and the declining price of crude. The first price change in crude during the year occurred on May 22, when a 25 cut was made. A second 25 cut was made July 12, and was followed by a 156 cut on .Aug. 28. This price held until Nov. 12, when there was a restoration of 156. On Dec. 17 a second 156 increase was put into effect, bringing the price to $I.So per barrel. Gas The large increase in the number of gas wells completed may be attributed to three factors; namely, the recently discovered production possibilities of moderately deep, hitherto little tested horizons, together with increased demand and price. The latter has been made possible by a recent decision of the court, which ruled restraining the public service Commision's prohibition of a raise in the minimum monthly charge to small consumers by one of the major gas companies. A portion of the revenue derived in this manner is being passed along to the producer in the form of higher prices in the field. This higher field rate will remain in effect until a new ruling is made, when it will be reduced in proportion to the reduction of the monthly minimum charge. In an effort to extend the chambers Dam Fifth sand oil pool southwest from Amwell township, Washington County, several wells have been drilled. One of these, in Morris township, washington County, had an initial of 3.2 million cu. ft. open flow from the Big Injun sand. This indicates an entirely new productive area for the latter horizon. Allegheny County had one spectacular well in South Fayette township-—at a depth of about 2500 ft. a 4-million-CU. ft.

Jan 1, 1941

By John T. Galey

Production of crude oil for 1940 in southwestern Pennsylvania was off nearly 70,000 bbl., largely as a result of the great number oi abandonments, together with the lack of extension of the Washington and Green County pools. Oil wells completed numbered 51, which is 26 more than last year, but the total initial production of 259 bbl. is only 18 bbl. greater than in 1939. There was an increase of 72 over last year for a total of 209f gas wells. However, 68 7 dry holes were drilled, which is 40 more than a year ago. Thus, 328f wells were drilled during the year, and rigs are erected or drilling is progressing on 59 t more. Shallow Development Oil.—Butler County led in number of oil wells completed, with a total of 27 for an initial production of only 69 bbl. Washington County, with 12 new oil wells, one of which made 40 bbl. from the Fifth sand in S. Franklin township, has 95 bbl., while in Allegheny County 9 wells gave an initial of 86 bbl. for the highest Per well average in the area. This initial was given a considerable boost by one 35-bbl and another 2;-bbl. well in West Deer township, where the Fourth sand produced at 1840 feet. Greene County had only one oil well completed during 1940, and Washington County had 12. The subnormal totals for these counties may be explained by the higher cost of completions and the declining price of crude. The first price change in crude during the year occurred on May 22, when a 25 cut was made. A second 25 cut was made July 12, and was followed by a 156 cut on .Aug. 28. This price held until Nov. 12, when there was a restoration of 156. On Dec. 17 a second 156 increase was put into effect, bringing the price to $I.So per barrel. Gas The large increase in the number of gas wells completed may be attributed to three factors; namely, the recently discovered production possibilities of moderately deep, hitherto little tested horizons, together with increased demand and price. The latter has been made possible by a recent decision of the court, which ruled restraining the public service Commision's prohibition of a raise in the minimum monthly charge to small consumers by one of the major gas companies. A portion of the revenue derived in this manner is being passed along to the producer in the form of higher prices in the field. This higher field rate will remain in effect until a new ruling is made, when it will be reduced in proportion to the reduction of the monthly minimum charge. In an effort to extend the chambers Dam Fifth sand oil pool southwest from Amwell township, Washington County, several wells have been drilled. One of these, in Morris township, washington County, had an initial of 3.2 million cu. ft. open flow from the Big Injun sand. This indicates an entirely new productive area for the latter horizon. Allegheny County had one spectacular well in South Fayette township-—at a depth of about 2500 ft. a 4-million-CU. ft.

Jan 1, 1941

Profiled here are the eight RMCMI 2000 Scholarship Award winners. Six of the eight attended the 96'' Regular Meeting and convention at the Sheraton Tamarron Resort in Durango, Colorado in late Tune. Each spoke during the Scholarship Awards Monday luncheon and shared their goals with attendees. In addition to receiving a 52,000 tuition credit, thanks to the Patrons of the Institute annual funding of scholarships, each received recognition at the luncheon with a brass plaque signifying this honor. The winners arc guests of the Institute Sunday through Tuesday noon and have an outstanding opportunity to meet many in the coat industry who could be potential employers. The state vice presidents host the winners and pay for their travel and hotel expenses. This is a continuing scholarship and may be renewed for tuition credit again in the senior year it the winner is a full time student and is recommended by the dean of the college or university. A resident from each of the eight member RMCMI states is selected by the Scholarship committee from Board approved institutions. Criteria for these annual awards is that the recipient (1) is a full time sophomore student who will use the tuition credit the junior year. (2) Be both a U. S. citizen and a legal resident of the member state. (3) Maintain good academic standing, be pursuing a degree in a mining related field and have an expressed interest in western coal as a possible career path. Contributions to this worthwhile project are tax deductible to each individual RMCMI member or his company. Through donations of $100 or more to the Patrons of the Institute, each Patron receives a plaque and a year bar for each additional year contributions arc made. There may be directed to RMCMI Patrons, 3000 Youngfield Street, #324, Lakewood, CO 50215. [ ]ARIZONA WINNER David L. Vatterrodt University of Arizona The son of Charlene and Larry Vatterrodt, David graduated from Marana High School, Tucson, Arizona where he attained a 3.6 GPA. In his second year at the University of Arizona he has a 3.4 GPA and is pursuing a Bachelor of Science in Mining Engineering. He is a member of SME and enjoys playing tennis and riding his motorcycle. He is the recipient of a $1,000 Tradition of Excellence scholarship. David volunteers every Saturday morning during the academic year at the U of A. San Xavier Mining Laboratory. His tasks there include work area inspections, jack-leg drilling, scaling, roof bolting, operating an LHD and overshot mocker, track laying and other general maintenance. COLORADO WINNER [ ]Jonathan B. Casten Colorado School of Mine. Graduating with high honors and a 3.99 GPA from Windsor High School, Colorado, Jon is well prepared for the rigors of academia. In high school he was on the Dean's list, Salutorian of the Senior Class, member of National Honor Society, Colorado Boys State delegate and lettered in varsity golf.At Mines, Jon belongs to SME and Work Study and maintains a 3.75 GPA. He enjoys golf, hiking and weight lifting. His parents are Katherine and Fred Casten of indsor. Jon has chosen Mining Engineering as a career as he plans to improve the nation's efficiency of extracting natural resources.

Jan 1, 2000

By L. Katgerman, R. Van Toi, H. E. A. Van den Akker

"Mould filling simulations are powerful tools for optimizing the characteristics of castings. The robustness of calculational methods for mould filling simulations is generally tested in simple geometries. While a vertical plate has been used often for validation studies, this paper aims at mould filling simulations of a horizontal thin wall casting. Such castings exhibit a strong interaction between heat transfer (solidification), surface tension and gravitational force.The results are presented of a study to validate numerical simulations of mould filling phenomena in a thin wall horizontal casting. Solidification during mould filling is studied computationally. Velocities are measured using Particle Image Velocimetry.INTRODUCTIONIn foundry practice Computational Fluid Dynamics (CFD) is being considered a promising tool to arrive at a better understanding of casting defects introduced during the mould filling period of a casting. The use of CFD is believed to be advantageous in predicting possible defect locations, pouring times, and the lowest possible casting temperature without the risk of cold shuts. In addition, CFD may be used to optimize pouring system geometries [1,2]. As opposed to experimental studies in, e.g., cold water models, CFD allows for the flexible modification of the casting geometry and the pouring system, and for the inclusion of physical effects such as solidification and heat transfer. Thus, a proper use of CFD may lead to a reduction of the casting rejection rate without expensive trial-and-error procedures, and to a decrease of production costs in foundries. Mould filling simulations take a special place in CFD, because a free surface tracking algorithm is required. Over the past decade methods, MAC [3] and SOLAVOF [4], have been extended to 3-D. The robustness of computational methods for mould filling simulations is generally tested in simple geometries [5,6]. While a vertical plate has been used often for validation studies, this paper concentrates at mould filling simulations of a horizontal thin wall casting. Thin wall horizontal castings exhibit a strong interaction between heat transfer (solidification), surfaces tension and gravitational force. The gravitational force in this setting is orthogonal to the plane of flow and has therefore no influence on the shape of the free surface in the plane of flow. Mould filling numerical methods and algorithms have been recently reviewed by Chen et al.[7]."

Jan 1, 1999

By P. C. O. Chukabarah

Atkinson's resistance square law is the cornerstone equation for traditional expression of energy losses in mine ventilation engineering. But the nomenclature for the various forms of energy losses are often confused for one another, misapplied or misinterpreted. These forms of energy were re-examined from thermodynamic and fluid-dynamic perspectives. Resultant expressions showed that both incompressible and compressible flow regimes in underground mines can easily be accommodated. Given the well-known three major energy forms, which are equivalent to one another but numerically unequal, corresponding equations to Atkinson's (pressure loss) for headloss and workloss were derived. The thermodynamic weight relational resistance ([w] s2/m5) associated with energy per unit weight (headloss) was dimensionalized for the first time. Also, normalized Atkinson-like equations for headlosses and worklosses were derived to ease direct computations in mine ventilation practice.

Jan 1, 1995

By D. N. Witman

One of the special uses to which the electric furnace has been put recently is the melting of an alloy of nickel and cast iron for the production of electrical-resistance grids. The metal sections of these grids, Fig. 1, are quite uniform for each pattern, but there is, among the various patterns, a variety of thicknesses. The cross-sections vary from 1/2 by 3/16 in. to as small as 1/8 by 1/8 in. The electrical resistance of a perfect casting lies within 10 per cent. above or below the fixed listed resistance for each pattern. Good molding is essential to success in the making of these grids, for with absolutely correct metal, a variation of 0.01 in. in width and thickness of section on some of the patterns may mean as much as 12 or 14 per cent. variation in resistance. The service for which these castings are intended demands that the metal, even in the smallest castings, be very soft, showing an open, gray, highly graphitic structure, in order that they may be resistant to shock, and stand up well under rough usage. The metal used for this purpose is a gray iron alloyed with 4 to 5 per cent. of nickel, which element, when the composition of the alloy is correct, imparts toughness and pliability to the metal and helps to overcome the tendency of metal to run white and become brittle because of the rapid cooling action of the sand mold. When cold, these castings can be twisted into various shapes, taking a permanent set without breaking. The alloy has approximately double the e1etrical resistance of ordinary cast iron. The metal specification is as follows: Per Cent. Silicon............................................. 2.40 to 2.60 Sulfur............................................. Under 0.05 Phosphorus......................................... Under 0.08 Manganese......................................... Under 0.40 Total carbon....................................... 3.60 to 4.00 Nickel............................................. 4.00 to 5.00 Copper............................................ 0.50 to 0.70

Jan 1, 1922

By D. N. Witman

One of the special uses to which the electric furnace has been put recently is the melting of an alloy of nickel and cast iron for the production of electrical-resistance grids. The metal sections of these grids, Fig. 1, are quite uniform for each pattern, but there is, among the various patterns, a variety of thicknesses. The cross-sections vary from 1/2 by 3/16 in. to as small as 1/8 by 1/8 in. The electrical resistance of a perfect casting lies within 10 per cent. above or below the fixed listed resistance for each pattern. Good molding is essential to success in the making of these grids, for with absolutely correct metal, a variation of 0.01 in. in width and thickness of section on some of the patterns may mean as much as 12 or 14 per cent. variation in resistance. The service for which these castings are intended demands that the metal, even in the smallest castings, be very soft, showing an open, gray, highly graphitic structure, in order that they may be resistant to shock, and stand up well under rough usage. The metal used for this purpose is a gray iron alloyed with 4 to 5 per cent. of nickel, which element, when the composition of the alloy is correct, imparts toughness and pliability to the metal and helps to overcome the tendency of metal to run white and become brittle because of the rapid cooling action of the sand mold. When cold, these castings can be twisted into various shapes, taking a permanent set without breaking. The alloy has approximately double the e1etrical resistance of ordinary cast iron. The metal specification is as follows: Per Cent. Silicon............................................. 2.40 to 2.60 Sulfur............................................. Under 0.05 Phosphorus......................................... Under 0.08 Manganese......................................... Under 0.40 Total carbon....................................... 3.60 to 4.00 Nickel............................................. 4.00 to 5.00 Copper............................................ 0.50 to 0.70

Jan 1, 1922