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By R. L. Crosby

From studies of wrought magnesium alloys containing rare-earth elements, data are presented on the mechanical properties of the alloys at room temperature and at temperatures of 100°, 200°, and 300° C. Results of studies of the solid-solubility of cerium and zirconium in magnesium as determined by electrical resistance measurements are also discussed and are compared with those of other investigators. The strength of magnesium-cerium alloys did not increase with the addition of vanadium and titanium dioxide. The addition of zirconium increased the tensile strength of the alloys as much as 10,000 p.s.i. at room temperature, but this increase diminished above 100° C.

Jan 1, 1962

By Charles K. Rose

The Cebolla Creek titaniferous iron deposits near Powderhorn in southern Gunnison County, Colo., were examined by the Federal Bureau of Mines as part of an overall program to investigate the Nation's titanium and iron resources. The deposits occur around the periphery of the Iron Hill stock, which underlies an area of about 12 square miles. Concentrations of magnetite, ilmenite, and perovskite arc localized along fractures in the pyroxenite stock. Mineralogical studies of composite surface samples collected in 1956 showed that most of the iron is present in ilmenite-bearing magnetite. Perovskite is the chief titanium mineral in the magnetite-rich and augite-rich types, and sphene is the principal titanium mineral in the placer material. The mica-rich rock contains approximately equal amounts of perovskite, ilmenite, and sphene.

Jan 1, 1960

By Kenneth J. Miller

To determine the effectiveness of the many new flocculants available to the coal industry 20 of these reagents were evaluated treating slurry feeds to four refuse thickeners. Settling rates and supernatant liquid clarities were determined for each of the flocculants on the four slurries, and zeta potential measurements of the slurry solids were made. The test results showed that the flocculants provided comparable results when judged categorically as anionic, nonionic, or cattonic. It was also apparent that control of zeta potential insures maximum benefit from a flocculant.

Jan 1, 1968

By John F. Papp

The Bureau of Mines has sampled microstructure of low-pressure flat flames by mass spectrometer for normal methane-oxygen-argon and for methane-oxygen-argon-bromotrifluoromethane flames. The physical and chemical phenomena, and the method of analysis of mole fraction data to evaluate net reaction rates are here considered in detail. Included is a computer program listing with output on one flame. Chemical species considered are CH4 , CO, CO2, H, H20, OH, Ar, H2, O2 , O, H2CO, CH3 , CF3Br, HF, HBr, Br, CH3Br, HCO, F2CO, CH2 CF2 , H02.

Jan 1, 1975

By J. G. Kirby

According to the Bureau of Mines annual survey, there were 319 petroleum refineries in the United States as of January 1, 1957 capable of processing 9,123,674 [ ]-barrels of crude oil daily. This was the first time in eleven years that the total number of refineries increased. The crude throughput capacity of the refineries increased 491,284 barrels daily (6 percent) above the January 1, 1956 capacity. The East Coast and Texas Gulf Coast refining districts accounted for 60 percent of the additional capacity installed. Three new refineries were put into operation on the East Coast during the year with a total daily crude throughput capacity of 154,434 barrels while the other refineries in the district report a net loss in capacity, installing equipment capable of processing 140,000 barrels, but dismantling equipment with a capacity of 150,100 barrels. In the Texas Gulf Coast district, one new refinery with a daily crude oil capacity of 5,000 barrels was placed in operation in 1956 and 143,700 barrels of crude capacity was added to existing refineries. The capacity of the average refinery to process crude oil increased from 27,145 barrels daily to 28,601 barrels in 1956.

Jan 1, 1957

By J. F. Barkley

Field tests were made on the rate of corrosion of 30 materials used in air preheaters under regular operating conditions, and the buildup of deposits was observed. Twenty-three materials were tested with coal as the fuel on an underfeed stoker and seven with oil, including a short period with pulverized coal as fuel, The plant equipment is described, and pertinent plant operating data are tabulated. Figures 17 and 19 (pp. 24 and 27) give the results of corrosion tests on the uncoated metal test specimens. The information obtained from these tests follows the general pattern described in Bureau of Mines Report of Investigations 4996, Corrosion and Deposits in Regenerative Air Preheaters. The deposits were similar, and the corrosion rates of Cor-Ten and Mayari-R steel (previously found to be essentially the same at the Harding Street Station using coal) continued to show little difference at the Marion Generating Station using principally oil. The one high-alloy steel tested, type 321, showed a much higher corrosion rate than the low-alloy steel, Cor-Ten.

Jan 1, 1959

By Gennaro G. Marino

The Bureau of Mines and the University of Illinois investigated surface characteristics and damage to structures from mine subsidence over a room-and-pillar coal mine in Hegeler, IL. Data on three adjacent subsidence sags and associated structural damage were collected, summarized and evaluated. The subsidence sags developed over a 10-year period and took place above a modified room-and-pillar operation mining the Herrin (No. 6) coal at a depth of 130 to 135 ft. Surface vertical displacements of 3.0 to 3.5 ft resulted from extracting 6.1 to 6.4 ft of coal. Ground movements associated with sag formation severely damaged three houses and a radio station building, broke numerous utility lines, and structurally distorted three radio transmission towers. The radio station was remodeled and the towers repaired, but the three houses were subsequently demolished. Surface waters collecting in the subsidence depressions caused failure of radial ground transmission systems. The following subsidence profile characteristics were determined at the radio station and one of the houses, respectively: profile slopes, 0.02 and 0.07; maximum curvatures, 2.3 x 10-4 ft-1 and 3.0 x 10-4 ft-1; and angular distortions, 6.6 x 10-3 and 62.0 x 10-3. Although the house was more severely damaged than the radio station, both structures are classified as severely to very severely damaged.

Jan 1, 1986

By Murray Greyson

A number of tests were made with various methanation catalysts in fixed-bed, conventional fluidized-bed, and multiple-feed, fluidized-bed equipment to develop catalysts and processes for methanation of synthesis gas. The results show: 1. Methanation reactions may be carried out in 1-inch, bench-scale equipment at high synthesis-gas throughputs with good temperature control of the reactions if a multiple-feed type of fluidized-bed design is used. 2. Nickel is superior to iron as a catalyst for the methanation of synthesis gas, unless the process is considered in terms of a combined operation that produces both gaseous and liquid products. 3. Techniques of catalyst preparation determine, to a large extent, the process life of nickel catalysts, and these techniques must be thoroughly investigated before any conclusions can be reached. 4. Enough data are available to indicate that the sulfur concentrations in synthesis gas that is used for methanation are extremely critical, and maximum process limits should be carefully evaluated.

Jan 1, 1955

By John P. McDonnell

Coal mine bounces and bursts are major problems facing U.S. mine operators. Bounces and bursts have the potential to inflict severe injury on mining personnel, damage equipment, and cause mine closures. High- stress conditions, at or near the working face, are the common denominator in the burst problem, If mine operators can locate high-stress and potentially burst-prone zones, they can then use stress-relief methods to control the burst condition. One method of locating the high-stress zone is the probe-hole-drilling or drilling-yield method. Probe-hole drilling is used frequently in Europe, the U.S.S.R., and Japan as a means for locating potential burst zones. Consequently, the Bureau of Nines performed tests in the laboratory and in a deep, burst-prone western mine to analyze probe-hole drilling. The in-mine method, very simply, involves drilling a hole into the coal seam and measuring the volume of cuttings obtained. A certain volume of cuttings can be expected from a certain diameter and length drill hole. A significant increase in the volume of cuttings means the zone around that particular hole is highly stressed. In-mine use of the drilling yield method has shown it to be a useful tool for locating highly stressed and potential burst zones. Results from laboratory testing confirm that high stress applied tri-axially to a cube specimen will cause a significant increase in the volume of cuttings from a small-diameter drill hole in the specimen.

Jan 1, 1988

This manual provides instructions for installing, operating, and maintaining a protective canopy on the Galis Mfg. Co. roof drill. The instructions are based upon two actual installations: one made in a mine on roof drill, model 300, and one in the factory. The parts list and engineering drawings for the protective canopy are included at the end of the manual. And a discussion of some alternative design concepts is also included. The manual can also be used for retrofitting other roof drills with similar protective canopies. Skilled mechanics can determine if the instructions herein would be applicable to the other roof drills and can determine any necessary modifications if they are not.

Jan 1, 1973

By David C. Byrne

From an engineering perspective an ideal industrial noise control solution focuses directly on the actual source of the poise. Eliminating the noise-generating mechanism altogether obviates the need for other noise contra l treatments or hearing protection devices. However, in cases where attenuating the source is not feasible engineering controls must be oriented toward blocking the path that the sound waves travel toward employees. Acoustical enclosures are commonly used as sound path treatments to contain the noise from a machine: alternatively a control room/booth or equipment operator's cab may be used to isolate the worker from the noise. Anyone who has successfully used acoustical enclosures knows that the design procurement, and installation process is deceptively simple. Alt too often First-time efforts fait to account for many of the constraints that can render the enclosure essentially useless. Things that cannot be overlooked include: providing convenient worker access (physical and visual): allowing for proper machine operation/product flow; and supplying fresh air or preventing undue heat or contaminate build-up inside the enclosure. All of these factors must be given careful consideration, otherwise the enclosure will not perform adequately.

By Joseph D. Davis

The term "fusain" was first adopted from the French by the American geologist J. J. Stevenson in 1911, according to Wheeler, (1),3 who applies it to that portion of coal resembling charcoal, which he treats as one of the four ingredients of banded bituminous coal. The term has since been adopted by American writers. The Germans use it with slightly different spelling - namely, fusit. It is the equivalent of "mother-of-coal" and "mineral charcoal" of the earlier British writers. The English word fusain is also applied to "a crayon of fine charcoal" and is derived from the Latin root fusus. OCCURRENCE OF FUSAIN IN COAL AND ITS RECOGNITION Fusain is fairly widely distributed in coals of all ranks in varying amounts. It is almost always present in very thin sheets between the bedding planes of the banded coal constituents and presents a jet-black silky appearance who n the coal is split away. As fusain has little cohesive power the coal splits readily along the planes where it occurs. Such fusain bands often attain appreciable thickness -- frequently 1/4 to 3/4 inch. -Beet (2) has reported a maximum thickness of 2 inches for fusain partings, and Sinnatt (3) has found it in the form of plates and lumps; one lump taken by him from the Peacock mine weighed 3-3/4 pounds. Bore (4) has found it in coal balls. Sinnatt (3) states that fusain occurs in two forms, "the first a hard compact variety occurring rather rarely, which can not be pulverized by pressure of the fingers the second type is the common substance" -- that is, a very friable, easily pulverized material. The writer has also found the two types of fusain in the same coal bed and has observed that the hard variety contained considerable calcium carbonate, which probably entered the material in situ by infiltration. Sinnatt further remarks that the layers of fusain (soft type) usually contain less moisture than the coal (or lose it more readily on exposure), and when exposed they quickly change to flocculent powder so that the fines of the coal as mined are likely to contain a major proportion of this substance.

Jan 1, 1929

By N. S. Dalal, X. N. Hu, X. Shi, V. Vallyathan

"Although silicosis has been studied extensively, the mechanism is still not fully understood. Experiments do provide evidence that the actions of unique properties of silica surface on the cell membrane are the starting point of silicotic processes. This paper summarizes literature on chemical properties of silica surface, and the effect of particle size on silica toxicity. This paper also discusses the ways in which silica dusts are thought to interact with the cell membrane, with emphasis on freshness, hydrogen bonding, and free-radical interactions.INTRODUCTIONSilicosis is a debilitating pulmonary disease that afflicts persons (miners, foundry workers, ceramic workers, heavy construction workers, etc.) who chronically inhale silica-containing dusts (Schepers, 1960; Silicosis and Silicate Disease Committee, 1988). Since silica is second only to oxygen in weight percentage of the earth's crust (about 28%) and is found in an enormous diversity of minerals, it is natural that silicosis is one of the major industrial health hazards all over the world. Although silicosis has. been studied extensively, the mechanism by which the dusts exert their toxic actions on cells and the processes by which these actions progress to fibrogenesis are still poorly understood. The biological characteristics of the dusts are largely unknown, although it is suggested that the dust size, shape, surface charge, roughness, surface chemical composition, trace metal content, and crystallinity; dose of silica in the ambient air of the workplace; duration of exposure; genetic variation in exposed subjects; personal respiratory patterns; and presence of any coexisting disease (such as tuberculosis or rheumatoid arthritis) all influence the expression of silicosis (Koskinen et al., 1983; Noweir et al., 1980; Raask and Schilling, 1980; Reiser and Last, 1979; Thorne et al., 1985; Wolff et al., 1981). The actual biochemical mechanisms through which these factors operate are still unclear. However, the experiments do provide evidence that the actions of certain unique properties of silica surface on the cell membrane are the starting point of the silicotic process (Allison et al., 1966; Allison and Harrow, 1971; Bateman et al., 1982; Marks, 1957; Parazzi et al., 1968; Reiser and Last, 1979; Summerton et al., 1977). This article summarizes literature on chemical properties of silica dusts and how silica dusts are thought to interact with the cell membrane, with emphasis on hydrogen bonding and free-radical interactions."

Jan 1, 1989

[~lis is the f'fth in a ~erieG of reports on properties of commercial motor fuels, made in accordance 1,'Vi t:h fl cooperative ae,ree-ment betwGon tho Cooperative Fuel ReRRarch (e.F.R.) Committee and the Bureau of I ines of the Dcpart~ent nf the Interior. The first report gave data on motor r-asolino~ sold during the wintor of 935-36.31 Thi~ report covers 84 brands of ga~oline represented by l,722 samples exclurling the Pacific Coast. T 3)Se J.rom th~. ?~'tcific Coast IV .ro avnrL)f:od b~r tho Pacific Coa!3t tecilnical group "bofore o8ing submi ttcd ruld arc p~.lbl:'shcd GX Gtl~r as they were submi tted. In some areas r~lJort~ . erc roceivod f~om ~ ix to eicht compD.l1ie~ on the same brands of gasoline. whoruar. in other areas only one company reported on a brond. Thut., it CU .. "! be senn that BO .. 0 uf the dnt ;.U'e more rCY>l'c entat vc thM others. The inclusion of r~0rts fro:n several ci tie. w' thin somo of tho di stricts has ir.rpr,)vcd the report by reducinc; tr.e numb~r of brand rcportel by only ono company. ]

Jan 1, 1938

[~lis is the f'fth in a ~erieG of reports on properties of commercial motor fuels, made in accordance 1,'Vi t:h fl cooperative ae,ree-ment betwGon tho Cooperative Fuel ReRRarch (e.F.R.) Committee and the Bureau of I ines of the Dcpart~ent nf the Interior. The first report gave data on motor r-asolino~ sold during the wintor of 935-36.31 Thi~ report covers 84 brands of ga~oline represented by l,722 samples exclurling the Pacific Coast. T 3)Se J.rom th~. ?~'tcific Coast IV .ro avnrL)f:od b~r tho Pacific Coa!3t tecilnical group "bofore o8ing submi ttcd ruld arc p~.lbl:'shcd GX Gtl~r as they were submi tted. In some areas r~lJort~ . erc roceivod f~om ~ ix to eicht compD.l1ie~ on the same brands of gasoline. whoruar. in other areas only one company reported on a brond. Thut., it CU .. "! be senn that BO .. 0 uf the dnt ;.U'e more rCY>l'c entat vc thM others. The inclusion of r~0rts fro:n several ci tie. w' thin somo of tho di stricts has ir.rpr,)vcd the report by reducinc; tr.e numb~r of brand rcportel by only ono company.]

Jan 1, 1938

By M. J. Spendlove

A progress report is presented on a research program in which an attempt was made to develop a practical sulfide-volatilization process for recovering tin from low-grade Bolivian ores. Shaft-furnace designs and operating techniques were studied in a series of experiments in which the objective was to sulfidize cassiterite to stannous sulfide, remove the stannous sulfide by volatilization, reconvert the stannous sulfide to stannous oxide, and collect the resulting fume. A shaft furnace was developed and operated in a final test in which many of the previous difficulties were surmounted. Since the supporting funds were exhausted at this point, the project was discontinued; recommendations for further improvements in furnace design and operation were made on the basis of interpretation of experimental results obtained in shaft-furnace experiments and other related studies.

Jan 1, 1955

By X. N. Hu, X. Shi, V. Vallyathan, N. S. Dalai

"Although silicosis has been studied extensively, the mechanism is still not fully under stood. Experiments do provide evidence that the actions of unique properties of silica surface on the cell membrane are the starting point of silicotic processes. This paper summarizes literature on chemical properties of silica surface, and the effect of particle size on silica toxicity. This paper also discusses the ways in which silica dusts are thought to interact with the cell membrane, with emphasis on freshness, hydrogen bonding, and free-radical interactions.INTRODUCTIONSilicosis is a debilitating pulmonary disease that afflicts persons (miners, foundry workers, ceramic workers, heavy construction workers, etc.) who chronically inhale silica-containing dusts (Schepers, 1960; Silicosis and Silicate Disease Committee, 1988). Since silica is second only to oxygen in weight percentage of the earth's crust (about 28%) and is found in an enormous diversity of minerals, it is natural that silicosis is one of the Major industrial health hazards all over the world. Although silicosis has been studied extensively, the mechanism by which the dusts exert their toxic actions on cells and the processes by which these-actions progress to fibrogenesis are still poorly understood. The biological characteristics of the dusts are largely unknown, although it is suggested that the dust size, shape, surface charge, roughness, surface chemical composition, trace metal content, and crystallinity; dose of silica in the ambient air of the workplace; duration of exposure; genetic variation in exposed sub¬jects; personal respiratory patterns; and presence of any coexisting dis¬ease (such as tuberculosis or rheumatoid arthritis) all influence the ex¬pression of silicosis (Koskinen et al., 1983; Noweir et al., 1980; Raask and Schilling, 1980; Reiser and Last, 1979; Thorne et al., 1985; Wolff et al., 1981). The actual biochemical mechanisms through which these factors operate are still unclear. However, the experiments do provide evidence that the actions of certain unique properties of silica surface on the cell membrane are the starting point of the silicotic process (Allison et al., 1966; Allison and Harrow, 1971; Bateman et al., 1982; Marks, 1957; Parazzi et al., 1968; Reiser and Last, 1979; Summerton et al., 1977). This article summarizes literature on chemical properties of silica dusts and how silica dusts are thought to interact with the cell membrane, with emphasis on hydrogen bonding and free-radical interactions."

Jan 1, 1989

By Harry R. Nicholls

Preliminary tests on presplitting rock in the presence of an in situ static stress field were undertaken to study the influence of a horizontal static stress field on the creation of a vertical presplit fracture plane. These tests indicated that it is easier to fracture the rock parallel to the in situ maximum compressive stress than in other directions. Instrumented shots indicate that the interaction of stress waves generated by the detonating charges is probably responsible for starting tensile fractures between shotholes and that expanding gases may propagate these initial cracks by a wedging action. The hole spacing for presplitting appears to be equal to the half wavelength of the stress wave. However, wider hole spacing appears feasible if the initial fracture is started by closer hole spacing.

Jan 1, 1966

By Don B. Hunter

The Bureau of Mines investigated the extraction of alumina from calcined kaolin by leaching with boiling RCI in a train of three 50-gal continuous, stirred reactors. Slurry discharged from the reactors con-tained an excessive amount of fines, which impeded solid-liquid separation. Autogenous grinding of coarse solids that accumulated in the reactors was the source of the fines. This report describes modifications to the reactors and to the operations that led to decreased fines generation and improved solid-liquid separation. Modifications to the reactors included custom-made impellers, the addition of a baffle system, a subsurface slurry discharge system, and slower rotation of the impellers. Concurrent testing of a continuous horizontal belt filter showed that the form filtration rates were increased from 350 to almost 1,000 Ib/h+ ft-2 when the modified reactors were used.

Jan 1, 1984

By Howard P. Hamlin, John W. Sweeney

Shales from 14 locations in Indiana were sampled , tested , and evaluated to determine feasibility of producing lightweight aggregates by rotary - kiln and sintering methods . Sampling procedures and the geology of the significant shale units are discussed . Preliminary testing was conducted in a muffle furnace , and continuous tests were made in a 16 - inch by 14 - foot rotary kiln . The aggregate weighed 37.0 to 47.2 pounds per cubic foot . Concrete cubes employing the aggregate were tested to determine the qualities of the concrete . Compressive strength of the concrete using seven bags of cement per cubic yard , after autoclave curing for 6 hours , ranged from 3,600 to 5,850 pounds per square inch . Four samples made suitable lightweight aggregate in the laboratory rotary kiln . Four samples tested by sintering methods made unsatisfactory aggregate .

Jan 1, 1965