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By Robert H. Schutz

This publication lists and describes devices approved jointly by the Secretary of Interior and the Secretary of Health, Education, and Welfare, under the provisions of [§]70.300-1, Part 70, Subchapter 0 of Chapter I, Title 30, Code of Federal Regulations (35 F.R. 5548, April 3, 1970), for use as respiratory protection against respirable pneumoconiosis-producing dusts. Included are type C supplied-air respirators approved under Bureau of Mines Schedule 19R and dust, fume, and mist respirators approved under Bureau of Mines Schedule 21B.

Jan 1, 1971

By Kunwar Pal, S. K. Tyagi, A. K. Pandey

"This study deals with the performance evaluation, technical and environmental aspects of different cookstove models (NIRE-02, NIRE-03 & NIRE-04). These cookstove models were designed, fabricated and evaluated following Bureau of Indian Standards (BIS) and their performance was compared from technical and environmental points of views. The theoretical efficiencies of all the cookstove models are found to be in good agreement with the experimental one. Also, the overall performance of these models is found to be in the order of (NIRE-04 > NIRE-03 > NIRE-02) which is also observed to be much better than that of the traditional cookstoves being used by the people in most of the developing countries around the world. The CO2 emission reduction from these models is found to be between 2.0-3.0 tons per household annually which is ultimately in good agreement with the experimental values.IntroductionMore than 2.5 billion people around the world depends on the biomass based resources for cooking and heating applications which includes wood, cattle dung, charcoal and agriculture residue [1,2]. Generally, people of rural area cook their food on unvented open fire, which burn biomass fuel inefficiently besides it creates many thermal and environment pollution hazardous causing health problems in the women and girl children due to more exposure of emissions. Also the consumption of biomass is very high as compared to the fossil fuels due to the fact that the large population of the developing countries lives in the rural area than that of in the urban area. It is estimated that about 3% of the diseases are caused due to incomplete combustion of biomass, which results in the around 1.8 million premature death every year including around 0.9 million death under five year of their age [3,4].Ramanathan and Carmichael [5] recently found that the black carbon of unburned smoke is playing a major role in global warming. The emission factors for different combinations of fuel and stove tested in China for direct and indirect GHGs as well as other airborne pollutants such as, CO2, CO, CH4, TNMHC, N2O, SOx, NOx, TSP etc. for a typical set of operating parameters [6]. The improved biomass cookstove technology came into assistance which is technically feasible, socially reliable and economically viable [7, 8]. The improved biomass cookstove not only reduces pressure on the biomass resource, but also reduces the environmental pollution and also minimize the time required for collection of fuel wood [9, 10]. Sharma et al. [11] emphasized on the adoption and large-scale propagation of efficient stoves to improve the health of rural women and to reduce the consumption of firewood and environmental pollution."

Jan 1, 2014

By R. H. Sweetser

AT the Buffalo meeting in October, 1898 (Trans., xxviii., 865), our Secretary, Dr. Raymond, in speaking of the obstacles he had encountered in securing contributions to the Transactions from members in practice, said: "It is the disinclination of many members to communicate incomplete or partial or preliminary results. They are going to write, ' some day,' a thorough and monumental paper; and meanwhile they prefer to communicate nothing. . . . It is the difficulty to which I have just referred that I have encountered in a wide correspondence with members, undertaken for the purpose of securing contributions of fact and opinion concerning the special subject of this discussion. . . . Almost none of them seem to recognize the value of preliminary, incomplete and indecisive reports of practice, as laying the foundation for a thorough inquiry." This remark was made in immediate reference to a discussion concerning blast-furnace tuyeres ; but, notwithstanding this appeal from the Secretary, little has been recorded regarding the distribution, the penetration, and the pressure of the blast at the tuyeres and inside the iron blast-furnace. I am therefore encouraged to contribute the following incomplete and crude observations of the blast-pressure inside the hearth. At the suggestion of J. H. Frantz, the General Manager of the Columbus Iron & Steel Co., a test was made at the East furnace of the company to determine whether there was any difference in blast-pressure at the different tuyeres. The apparatus used for this test was not sensitive enough to give accurate results. It consisted of a small pressure-gauge mounted on a 3/8-in. gas-pipe. A hollow plug, fitting into the peep-hole of the tuyere-cap, prevented the blast from blowing-out during the test. The test-pipe was held in place by means of the handle on the outer end.

Mar 1, 1909

By Robert H. Richards

The extent to which sizing by sieves should be carried, as a preliminary to the separation, by jigging, of minerals of different specific gravities, has been a matter of controversy for many years. The subject has been investigated by several authorities, yet the ground does not seem to have been completely covered, nor are the questions involved entirely settled. For my present purpose I shall refer to but three investigators—Rittinger, Munroe, and Hoppe. In seeking additional light, I have gone over part of the old ground which has been considered satisfactorily settled; and since these preliminary tests have thrown light on some points, they have been included in this paper. In the investigations here described, I have confined myself, for several reasons, wholly to small sizes—grains of 0.1 inch in diameter and less. Rittinger's work was mainly done upon larger sizes, and there is much need among millmen of information concerning the smaller sizes. Moreover, these sizes brought the investigation within the means at my disposal. The laws that have been claimed as the laws of jigging by the several authorities are: 1. The law of equal-settling particles. 2. The lam of interstitial currents. 3. The law of acceleration. 4. The law of suction. The first of these has been considered by investigators, generally, to be the most important of all, and the larger part of the work of jigging is thought to be governed by it. But that it does not cover the whole of jigging is clear to all; and to account for the increased efficiency which we may call the extra jigging-catch, the other three laws have been advanced. The investigation described in this paper was undertaken to determine, as far as possible, to what extent each of the four laws con-

Jan 1, 1895

By R. P. Alger, M. P. Tixier, D. R. Tanguy

In the combination induction-electrical log used at present in the field, the induction logging tool is appropriate for the investigation of moderately invaded formations. A new induction sonde with a radius and investigation about twice as large has been developed recently for the case of deep invasion. It has very nearly the same vertical resolution as the present sonde so that thin beds are defined as accurately as before. The characteristics of the new tool are described, the corresponding interpretation charts are given and field examples are discussed. The design of the sonic logging tool has been modified to improve the calibration and the reliability. The fact that porosity can be accurately recorded by means of the sonic log has prompted new interpretation procedures for saturation estimation, wherein the data concerning the various permeable beds in a given well are correlated. One approach consists of plotting transit time vs true resistivity, with an appropriate scale. With this approach, saturations can be estimated conveniently even in cases where formation water resistivity is not well known. In another approach, a comparison is made of the values of the formation waters computed from the re- sistivity and sonic logs. Using the concept of continuity, this procedure makes possible a quick determination of zones of saturation in shaly sands and/or in case of appreciable variations of formation salinities with depth. It has been found that the comparison of porosity from the sonic log with the apparent porosity computed from a short-investigation resistivity log may reveal, in many cases, the presence of residual oil and thus detect potentially productive formations; this procedure is valuable when the true formation resistivity and the resistivity of the formation water are in doubt. INTRODUCTION During the past year, the efficiency of log interpretation has been vastly improved. The improvements have largely resulted from the introduction of a deep-investigation induction device and from the application of new interpretation techniques that utilize sonic vs resistivity readings. Since the new interpretation techniques depend, in part, upon good values of true formation resistivity, the new induction log will be discussed under Part I. The sonic interpretation techniques will be studied under Part 11. Early in 1959, the 6FF40 induction equipment was introduced in the field. This device was designed for a better approach to true formation resistivities in deeply invaded zones. The greatly improved radial investigation of the 6FF40 equipment has been achieved without sacrificing vertical resolution. The first combination induction-electrical log, the 5FF40, was introduced as a standard tool in 1956 for the logging of wells drilled with fresh muds. The tool has received wide industry acceptance in the United States. 'The 5FF40 induction log has a radial investigation sufficient to overcome average depths of mud filtrate invasion. At 5d invasion, for example, the 5FF40 induction log will read about 1.4 R. in a water sand where R., = 10R,. At 10d invasion, such induction log would read 2.45 R. in the same water sand. In either case, the effects of invasion would not be sufficiently great to cause a water sand to be mistaken for a shale-free oil- or gas-producing zone. Some formations, however, invade deeply — in excess of 10d. Such water zones could be mistaken for oil-or gas-saturated sands unless the porosity balance' can clearly make the distinction. It is for these deeply invaded formations that the 6FF40 was developed. CHARACTERISTICS OF THE 6FF40 Radial Investigation Characteristics To describe the comparative responses of the 5FF40

By H. Foster Bain

Jan 1, 1910

By Henry W. Edwards

Concrete is not a new, nor even a modern substance. Important structures built by the old Romans before the commencement of the Christian Era are to-day sound and solid— for example, the dome of the Pantheon in Rome, 142 ft. in diameter. I do not propose, therefore, to discuss the durability of the material, as in the mining and metallurgical business, structures, as a rule, are not calculated to endure for two thousand years. I do wish to urge, however, that much of the stone masonry around mines and smelters would have given better results if concrete had been used in place of stone. Concrete looks better; is stronger, cheaper, more durable, more quickly built, and above all requires no skilled labor, except that of the carpenter, who, like the poor, is always with us. Well proportioned concrete, that is to say, having well proportioned ingredients, may be safely relied upon to withstand a compressive or crushing strength of 50 tons per square foot. In most American cities, however, the building laws limit it to the absurdly low figure of 16 tons. This restriction is probably due to the political influence of the building-trades unions, which object strongly to its too free use, undoubtedly owing to its not requiring the services of skilled workmen. I hope to show that quite important construction work may be' undertaken without the aid of the gentleman with the trowel. In some of the isolated districts of the West and Southwest this is no mean advantage. The weight of good concrete, dry, is from 130 to 160 lb. per cubic foot. Ingredients of Concrete. Concrete is composed of four ingredients; viz., 1. Crushed Stone; 2. Sand; 3. Cement; and 4. Water.

Jan 1, 1905

By B. Vasanthakumar, H. Ravishankar, S. Subramanian, J. Braun

The flotation of sphalerite and galena in the presence of intra- and extra-cellular components isolated from Bacillus circulans before and after adaptation to the chosen minerals has been studied. Based on various biochemical treatments, the key biomolecule primarily responsible for the flotation of sphalerite has been identified as DNA, which functions as a bio-collector. A noteworthy finding is the considerably higher flotation recovery of sphalerite obtained in the presence of single stranded DNA (79.8%) vis-à-vis double stranded DNA (50.2%). Selective flotation tests using the soluble fraction obtained after thermolysis treatment highlight that sphalerite-adapted cells yield a higher selectivity index (S. I.) of 31.2 compared to galena-adapted (S.I. 4.3) or unadapted (S.I. 12.2) cells. During bacterial adaptation to the above chosen minerals, the quantitative and qualitative changes in the surface potential, surface morphology and cell wall components have been monitored. The prior adaptation of the bacteria to sphalerite results in the secretion of a higher amount of proteins, eDNA and phosphate, whereas adaptation to galena leads to a higher amount of polysaccharide, uronic acid and acetylated sugar, vis-à-vis the unadapted bacteria. A significant observation is that the bacteria undergo a change in morphology from rod to sphere as a strategy to resist metal toxicity during adaptation to galena. Interestingly, this phenomenon is not observed during bacterial adaptation to sphalerite. This morphological transition has been shown to involve changes in crucial cell wall components as well as changes in the levels of expression of bacterial cytoskeleton element mreB gene involved in the maintenance of the rod shape. The sequence of B.circulans mreB gene has been identified using Polymerase Chain Reaction (PCR) followed by DNA sequencing.

Jan 1, 2014

By David J. Hoadley

This report describes the development and underground operation of a semi-automatic, raise climber, Man and Supply Hoist System designed for stope access in underground metal and nonmetal mines. Demonstrated capabilities of the system include a 4000-lb payload capacity, control from the traveling cage and from up to five remote stations, operating in vertical or inclined raises 5 ft in diameter and up to 300 ft in length and a travel speed of 50 ft/min. The 'system has the capability of operating in crooked raises because the conveyance climbs two stationary wire ropes suspended down the raise. The drive unit is electrically powered with power and control signals supplied to the drive unit through an armored cable also suspended down the raise. The system has been designed for portability, ease of installation and minimum raise development. The system can be installed by two men in five shifts. The hoist has been demonstrated successfully in two underground applications. The first demonstration was in a 5-ft diam, 60 deg inclined raise over a 2-month period. The second demonstration utilized a vertical 5-ft diam borehole to access a blast-hole stoping area. The system successfully provided two shift-a-day service over a 7-month duration demonstration. This report provides a detailed description of the hoist design and its demonstrated performance in two mine applications.

Jan 1, 1981

By Jaime Gómez, María Luisa Pecho

El presente trabajo de investigación aplicada tiene como fin dar a conocer los hallazgos experimentales obtenidos, a niveles de laboratorio y de Planta Piloto, sobre el comportamiento de los sulfuros comunes en la flotación con agua de mar

Sep 30, 2022

By Min Chen, Lei Xu, Liang-yu Jin, Xue-liang Yin

For the purpose to reduce the high cost and heat storage loss of Al2O3-MgO bricks used as ladle linings, Al2O3-MgO-CaO bricks with lower theoretical density were fabricated and the densification behavior as well as mechanical property of this refractory was investigated. With addition of CaO, the initial sintering temperature of Al2O3-MgO refractory was decreased from 1300 to 1100°C associated with the expansive formation of CA2, and the compressive strength was also enhanced owing to the formation of bond linkage between CA6 and spinel. At high temperature, brick with 4% CaO content showed poor sinterability with high porosity because of the formation of platelet structure of CA6 grains, whereas brick with 8% CaO content was well sintered with higher relative density but lower bulk density than Al2O3-MgO brick, indicating that the densification as well as lightweight of Al2O3-MgO refractory was effectively promoted.

Jan 1, 2015

By Juan Patricio Ibáñez

Separation of arsenic and copper from Cu-As-H2S04 electrolytes by electrodialysis has been investigated at room temperature. The effects of current density and pH were studied. An arsenic-free copper solution was obtained for all the tested conditions. The transport efficiency for copper ions was found to be higher than 98% after 3 hours' test. Transport of arsenic and copper through the ion exchange membranes was increased by increasing pH and current density. Solution pH was found to be a key parameter for the separation process, since it controls the speciation of the ions to be transported and the formation of unwanted precipitates which reduce the global efficiency of the electrodialysis process. The main conclusion is that electrodialysis is a promising technique to be used in separating and/or concentrating ions of interest in copper electrometallurgy.

Jan 1, 2003

By J. D. Pennock

About a year and a half ago, Mr. Morris, an engineer of the Solvay Process Company, was sent to Belgium and France to study the manufacture of coke in the Semet-Solvay ovens, which were in operation at Havre. With complete plans of construction and a good understanding of the methods of running the ovens, he returned to Syracuse. Work on twelve Semet-Solvay ovens was immediately begun. These ovens, with plant for crushing and washing coal, and the necessary condensers, scrubbers, and concentrator for the recovery of the byproducts are nearly finished, and will soon be in operation. As the work approached completion it became necessary to determine what coal should be used. Accordingly, a chemical investigation of the various bituminous coals was made. I. Investigation of Coals. The samples of coal taken for analysis were: I. A sample of Reynoldsville coal that had been exposed to the weather for a year; 11. Reynoldsville coal taken from a car direct from the mine; 111. Morris Run lump coal; IV. Morris Run fine coal; V. Coal from the Fairmount Coal and Coke Company; VI. A special enginecoal from Pardee colliery, Phillipsburg, Pa.; VII. South Fork, Pa., coal; VIII. Coal from Laceyville, Ill.; IX. Pittsburgh bituminous coal from Ocean mines (gas-coal); X. Steubenville, Ohio, coal; XI. Evansville, Indiana, coal; XII. Coal from the Ohio Coal Company. Proximate Analysis. I. 11, 111. IV. V. VI. Water at 90° C.,* ..................................... Volatile,. .. 31.14 33.00 17.73 18.12 37.20 23.86 Fixed Carbon,. . 64.49 58.07 71.92 71.89 56.68 73.00 Ash,. .. 4.37 8.93 10.35 9.99 6.12 3.14 Coke,. .. 68.86 67.00 82.27 81.88 61.88 76.80

Jan 1, 1893

By J. H. Frye, J. W. Caum, R. M. Treco

IT has been suggested that: "Insofar as the hardening due to a solute depends upon the increase of lattice parameter produced by it, it is reasonable to suppose that this hardening might be related to the resistance which the pure solvent would offer to increase in its parameter."' It was further suggested that this hypothesis might be examined by comparing the hardnesses of analogous silver and copper alloys, since the stress necessary to produce a given lattice expansion is quite different in the two metals. Suitable data2,3,4 are now available on these alloys, and we shall proceed to an examination of the hypothesis quoted above. Hardness, Lattice Parameter and Ionic Overlap Increase in ultimate Meyer hardness has been plotted against increase in lattice parameter in Figs. I and 2. It is believed that most of the values are accurate within the limits indicated by the rectangles. These data are also presented in Table I. Ultimate Meyer hardness, P u, is defined by the equation: where L = load, D = diametei of an impression having the same diameter as the testing ball, which in this case is 4 mm. Increase in lattice parameter is defined as the difference between the lattice parameter of the solid solution and that of the pure solvent. The curves in Figs. I and 2 are based on equal solute concentration and an equal degree of plastic deformation pro duced by the testing ball. Hardnesses are corrected to a constant grain size for copper and silver alloys, respectively, and these two grain sizes are approximately equal. Furthermore, all solutes are from the same period of the B subgroup of the periodic table as their solvent. The question arises as to whether Or not lattice parameter is the only factor controlling the hardness of these alloys. There

Jan 1, 1943

By J. H. Frye, R. M. Treco, J. W. Caum

IT has been suggested that: "Insofar as the hardening due to a solute depends upon the increase of lattice parameter produced by it, it is reasonable to suppose that this hardening might be related to the resistance which the pure solvent would offer to increase in its parameter."' It was further suggested that this hypothesis might be examined by comparing the hardnesses of analogous silver and copper alloys, since the stress necessary to produce a given lattice expansion is quite different in the two metals. Suitable data2,3,4 are now available on these alloys, and we shall proceed to an examination of the hypothesis quoted above. Hardness, Lattice Parameter and Ionic Overlap Increase in ultimate Meyer hardness has been plotted against increase in lattice parameter in Figs. I and 2. It is believed that most of the values are accurate within the limits indicated by the rectangles. These data are also presented in Table I. Ultimate Meyer hardness, P u, is defined by the equation: where L = load, D = diametei of an impression having the same diameter as the testing ball, which in this case is 4 mm. Increase in lattice parameter is defined as the difference between the lattice parameter of the solid solution and that of the pure solvent. The curves in Figs. I and 2 are based on equal solute concentration and an equal degree of plastic deformation pro duced by the testing ball. Hardnesses are corrected to a constant grain size for copper and silver alloys, respectively, and these two grain sizes are approximately equal. Furthermore, all solutes are from the same period of the B subgroup of the periodic table as their solvent. The question arises as to whether Or not lattice parameter is the only factor controlling the hardness of these alloys. There

Jan 1, 1943

By Luis Landajo

El presente artículo describe el uso de técnicas modernas de administración y su aplicación en las industrias siderúrgicas. Dentro de este grupo, aquellas relacionadas con la investigación operativa son las más importantes - en tanto examina la toma de decisiones, formula políticas y ejerce control de la dirección en sí misma. Asimismo, las resoluciones que esta técnica emplea para los problemas encontrados son: en el caso de inventarios, la técnica que se utiliza es el lote económico, teorías de existencias, programación lineal (P. L.), programación cuadrática, programación dinámica; para la asignación, se aplica la programación línea!, la distribución o transporte, la asignación; para la espera en fila, las teorías de colas, teorías de secuencias, teorías de balanceamiento de líneas; para las fallas y reeemplazos se aplica la teoría del mismo nombre; la competencia se emplea la teoría de juegos, el modelo P.L y la teoría de decisión, y finalmente para el planeamiento; se emplea CPM, Pert, MAP.

Jan 1, 1967

By Sara J. Davenport

With the increased demand for mercury incident to preparations for national defense and the reduction in imports from some of the usual sources owing to war conditions, many small mines in the United States Pure now being worked that ordinarily would be unprofitable. This is indicated by the following table on mercury produced in the Unite States in 1939-40 (1)4/

Jan 1, 1941

By D. Bahrami, G. Danko

Spatial and temporal temperature and humidity variations for 5000 years are simulated in an emplacement airway within the conceptual, high-level nuclear waste repository proposed to be built at Yucca Mountain, Nevada. A multi-scale model is configured using MULTIFLUX, a thermohydrologic-ventilation code. The predicted surface temperature of most waste packages during post-closure exceed 140oC, the threshold limit known for likely localized corrosion for Alloy 22 waste package material. Small amounts of infiltration airflow through the mountain in Panel 5 are found to transport liquid water condensate to some of the waste packages emplaced along the peripheral section of the drift due to edge cooling.

Jan 1, 2004

By Robert Hunt

The American Institute of Mining and Metallurgical Engineers was the first American technical organization to consider steel-rail specifications and sections. If I am not mistaken, the first contribution on those subjects to the Proceedings of the Institute was presented by Prof. Thomas Egleston, in 1874, and was entitled "Investigations on Iron and Steel Rails made in Europe in the Year 1873.1" The next contribution was Dr. C. B. Dudley's report of his investigation for the Pennsylvania Railroad of the wear of steel rails in their tracks, in 1878, which contribution led to a very memorable discussion that extended through several meetings.2 In 1880, Mr. C. P. Sandberg3 presented an article on rail specifications and inspection and rail sections. This was followed, in 1881, by A. L. Holley,4 in his exhaustive report on the then used American rail sections. The next contribution, I believe, was made by myself' at the Buffalo meeting, in 1888, on steel-rail specifications, which I followed,6 in 1889, by a paper on steel-rail sections. Since that time there have been numerous contributions to the Transactions of the Institute in relation to the manufacture of steel rails. The American Society of Civil Engineers officially took up the investigation of the relation of rail sections to the wear of car wheels in 1888. In the prosecution of this work, the Society appointed a special committee, whose labors extended through several years and resulted in an exhaustive report to the Society in 1893.7 Later, another committee was appointed to consider specifications for the manufacture of steel rails; the labors of this committee extended over a period of several years, a final report8 being made in 1910. It was my fortune to be the secretary of both of those committees.

Jan 9, 1919

By J. D. Cooner

Since my working life of 32 yr has been spent in and about the anthracite mines of the Hudson Coal Co., and the previous 4 yr in a college school of mines, I can write best about the safety program of a coal mining company. However, most of the suggestions, statements and practices mentioned herein are applicable to the members of a safety organization and program of almost any industry. It is realized that industrial officials actually interested in real safety work are fully acquainted with the requirements of a practical safety program. Therefore, for such persons there may be nothing new in this paper. The Hudson Coal Co. of Scranton, Pa., employs 7000 men and produces 5,000,000 tons of anthracite annually at nine collieries scattered for a distance of 40 miles throughout the Lackawanna and Wyoming valleys of northeastern Pennsylvania. For the past 17 yr of the above mentioned 32, I have been engaged in safety work as a safety inspector, assistant mine superintendent, and at present the safety engineer. I have also had the privilege of visiting coal and metal mines in other parts of the United States and Canada. We Americans are the most careless people in the world. If any one doubts this statement why are 100,000 of our people killed accidentally annually? Or why during the almost four years we were engaged in World War II were more of our people killed accidentally at home than were killed in our army, navy, marine corps, coast guard, and other services during the same period? We are careless everywhere— in our homes, on the highway, at work and at play. The purpose of this paper is to outline the requisites of a safety department and its program to stop the accidents occurring to employees at work in mines or industrial plants. The first requisite for a safety program is that the management must be convinced of the need and value of a real safety program. By "management" is meant each department head from the president down. Otherwise a good safety department with a good safety program will not succeed because it will not have the proper personnel and equipment to work with, its rules and regulations will not be enforced, and the members of the safety department will be belittled in the eyes of most of the workmen and supervisors. Next, a safety engineer and his inspectors should have worked in the production end of the mines as workmen and also in an official capacity. They are then in a position to have practical and first hand knowledge of the accident hazards of the industry, how to prevent them, and in general the problems of both the workmen and officials. Some men are appointed as safety inspectors when they are physically unable to carry on as mine officials. Such men may know the safety end of the industry and even be safety-conscious, but if they are physically unable to be mine officials they are also physically unable to be safety inspectors, as a safety inspector in our mines must walk from 2 to 4 miles on each daily inspection and visit each working

Jan 1, 1949