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By E. D. Gardner

Oil shale, a long-considered potential source of motor fuel in the United States, is found over an extensive area in the Green River formation in Colorado, Utah, and Wyoming.4/ Oil has been retorted commercially from shale in Scotland for many years,5/ and work done by the Bureau of Mines and other investigators has shown that it is technically feasible to extract oil from American shales.6/ By refining, the shale oil may be converted into marketable products similar to those manufactured from crude petroleum. The present paper, which was finished in 1936, discusses methods that would be adaptable to mining certain American shales, and the treatment applies specifically to conditions iii the Green River formation on Naval

Jan 1, 1942

By H. S. Auvil

[The shrinkage of coke after formation is one of the variables that effects the net expansion of the change in both industrial and test ovens. Various test results5/ have been interpreted as indicating that cokes from certain coals shrink to a marked extent and that other cokes show very little shrinkage; but no comprehensive experimental study of the shrinkage of coke after its formation and of the factors influencing this shrinkage has come to the attention of the authors.]

Jan 1, 1940

By James M. Spear

The U.S. Bureau of Mines conducted a mineral survey of the Domeland Addition (5207) and Woodpecker (5206) RARE II areas during the summer of 1979. These study areas were examined to determine the presence or absence of mineral resources and reserves and where possible, to estimate values. The study areas are 9 air mi northeast of Kernville, California, and encompass 47,400 acres of primarily granitic rocks of the Sierra Nevada batholith with some scattered exposures of older metasedimentary, volcanic, and metavolcanic rocks. These other rock units partially surround the exposed batholith in the Domeland Wilderness and consist mostly of late Paleozoic quartzites, mica schists, marbles, and meta-volcanics, Mesozoic quartz diorite and gabbro intrusives, and local Tertiary basalt and andesite flows.

Jan 1, 1981

By J. R. Nettle

The purpose of these studies by the Federal Bureau of Mines was to determine the feasibility of refining low-grade hafnium by an inert-gas-shielded molten-salt electrorefining technique to produce a hafnium metal meeting reactor specifications. The techniques were adapted from those used success-fully for titanium electrorefining. Three electrolytes containing hafnium chlorides were developed from which deposits having a Brinell hardness of 170 or below were recovered. A KC1 + NaC1 + HfC14 electrolyte produced deposits in the hardness range of 140 to 165 Brinell. Deposits with a hardness range of from 132 to 152 Brinell were pro-duced from an electrolyte composed of KC1 + LiC1 + HfC14. A third electrolyte composed of NaC1 + K3HfC17 produced deposits with a hardness as low as 139 Brinell. In a fourth electrolyte, composed of NaC1 + K2HfF6, a measure of refining was accomplished, but under the test conditions no metal meeting specifications was recovered; none was softer than 174 Brinell. A number of metallic impurities were reduced in quantity by the electro-refining process, notably iron, which normally was reduced from 250 p.p.m. to less than 50 p.p.m. Magnesium generally was reduced from 680 p.p.m. to less than 80 p.p.m. Manganese content was also reduced by the electrorefining process. Sponge containing 90 p.p.m. Mn yielded deposits containing a maximum of 50 p.p.m.; some deposits contained only 10 p.p.m.

Jan 1, 1961

By Frank M. Vodoklys

This is the final report on Contract H0220049 covering the period from 27 April 1972 to 30 April 1974. The objective of the contract was to develop and evaluate materials and methods to achieve post explosion identification of explosives reliably and economically through the use of phosphor coded grains incorporated into the explosive during its manufacture. A coding system of two spotting phosphors and seven coding phosphors was successfully developed during the execution of the contract. The ability of the coded grains to survive detonation in many different types of explosives was demonstrated and the complete code was extracted from a single 100 micron post-explosion fragment. A method was established for testing grain strength to correlate with field test results and an optical system was designed for extracting the code from the grains. Also in fulfillment of the contract requirements a laboratory method for manufacturing the coded grains was established and ten one-pound samples, each with a different code, were fabricated. Finally, a method was developed for applying a coating of polyethylene to the grains to prevent sensitization of the tagged explosives and the ten one-pound samples were coated and delivered to the Bureau of Mines.

Jan 1, 1974

By J. S. Dunning

One Federal Bureau of Mines research goal, to minimize requirements for domestically scarce mineral commodities through conservation and substitution, can be accomplished by utilizing more abundant elements such as iron, molybdenum, and titanium. An example of this research is the study of precipitation-hardening, iron-base alloys containing molybdenum and titanium, as substitutes for the high-tonnage stainless steels that are high in imported nickel and chromium. The precipitation hardened iron-base alloys are strengthened by a dispersion of the ternary Laves phase, Fe2 (Mo, Ti). Aluminum and chromium additions changed the solid solubility limits of molybdenum and titanium in a-iron and affected the composition of precipitating phases. A baseline composition of Fe-7Mo-2Ti was selected to study the effects of aluminum and chromium additions on the precipitation-hardening mechanism and microstructure and was also used in studies of mechanical properties and oxidation resistance. The study yielded workable, precipitation-hardening alloys, with elevated temperature strengths equivalent to or superior to types 304 and 316 stainless steels. Chromium and aluminum additions in combination were more effective in providing oxidation resistance than either addition was alone.

Jan 1, 1980

By K. E. Stanfield

[Asphalt ~~d road oil ar8 the principal products manufactured from Wyor.1in~ Ilblack oilo" \r,hich, beca.use of th?lir hig.~ E\.sphal t and hig} sulfur COi.1Jce~1t, .!?re difficult e':ld costly to refine into hi?;h-gra.de motor f 101s, burning oils. and lucri ants by presont mothods. Accordin~ly. the demand for truHle asphaltic renidl urn for the construction of roade aJ1.d other uses is 3. controlling factor in the quantity of crud~ oil prod ICed. The increasiilg -u.tilization of special aST>ha.lts as ine}""Pensive bonding, in-]

Jan 1, 1941

By John Kosek

The electrochemistry of carbon monoxide, nitric oxide and nitrogen dioxide was investigated at a variety of electrode materials in different supporting electrolytes. A portable detector for carbon monoxide was developed using a porous gold anode in perchloric acid supporting electrolyte. This detector has two full scale ranges, 0-100 ppm and 0-500 ppm. A portable detector for mixtures of nitric oxide and nitrogen dioxide was developed using a porous silver cathode in sulfuric acid supporting electrolyte. Nitrogen dioxide was determined in the gas stream by electroreduction. The nitric oxide in the gas stream was oxidized to nitrogen dioxide by passing it over Cr(VI) on firebrick. Electroreduction gave the sum of NO + N02. Analog circuitry was used to display the amounts of NO and N02 separately. Two ranges were available for each gas. They were 0-10 and 0-50 ppm for NO and 0-2 and 0-10 ppm for N02.

Jan 1, 1979

By Stan Henning

The monthly summary of the climatological record for the demonstration mine is presented in Table 1. Tear normal temperatures occurred throughout the growing season. From May to October precipitation was more than normal except in June when it was 2.55 inches below normal. Corn and soybean plantings were delayed until June 2-7 because of wet field conditions. This is about one month later than normal for corn planting. Insect infestations were much less than those encountered in previous years. Cutworm activity was not noticed and alfalfa weevil infestation were small and patchy. Stalk rot in corn was a significant problem at harvest and resulted in much Milk lodging. The wet and generally overcast conditions of July, August and September were bend 10 beneficial al to certain plant disease organisms. For example, pumpkins planted in a small garden area at the demonstration mine did not ripen because of a powdery mildew resulting from overcast, wet conditions. Field operations and row crop plantings were greatly delayed by wet field conditions. It was difficult to plant by conventional tillage because the soil remained soft and sticky where the moldboard plow had been used. Plots in the no-tillage system could he planted before conventionally tilled plots could be traversed. Plant emergence and plant density at

Jan 1, 1982

By Rudolf E. Grauer

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Jan 1, 1981

By P. Nicholls

Patent records show that the idea that the burning of fuels can be improved by mixing or pretreating them with chemicals 6 dates back to the early years of the last century. By 1845, English and French patents included the specific beneficiations of elimination or reduction of smoke, soot, and clinker; reduction of the ashes, presumably meaning the total weight of refuse from the ashpit; elimination of sulphur fumes; increase in the rate of burning; increase in the time a given charge of fuel would last; and, in most patents, a saving of fuel. The earlier patents specified additions up to 80 pounds or more per ton of fuel, but after 1860 the quantity was rarely more than 4 pounds. There is no record of the extent to which these patents were commercialized, but after 1884 many American patents were assigned to companies specializing in treatment of coal, so it is probable that the products were marketed on a considerable scale at least as early as that date. From 1900 on, many companies marketed proprietary products that were sold under the general name of "fuel savers." Since its establishment in 1910, the Bureau of Mines has continually received inquiries about these products and, at the request of other govern-mental departments, has tested some used in accordance with the instructions of the purveyors; the results were all negative and, within the accuracy of measurements, the products had no effect on the burning.

Jan 1, 1937

By Engelmann. William H.

In pursuit of innovative methods to improve mining productivity, the Bureau of Mines is investigating the use of inorganic salts as drilling fluid additives for penetration enhancement. Laboratory diamond drilling tests were performed on Westerly Granite with aluminum chloride solutions and on Sioux Quartzite with aluminum nitrate and aluminum, calcium, sodium, and zirconium chloride solutions as drilling fluid additives. These drilling results were compared with the average drilling performance using distilled, deionized water on Sioux Quartzite (12 replicate tests) and Westerly Granite (3 replicate tests). Maximum in-creases in penetration per given time and bit life were obtained when drilling with zero point of charge (ZPC) concentration solutions of each additive. For Sioux Quartzite, maximum increases in penetration and bit life ranged from 96 to 115 pct and 64 to 99 pct, respectively. For Westerly Granite, maximum increases in penetration of 155 and 165 pct and bit life of 109 and 136 pct were obtained at or near ZPC aluminum chloride concentrations of quartz (7.3 x 10-7 mol/L AIC13) and alkali feldspars (1.1 to 1.5 x 10-6 mol/L AIC13), respectively. This simultaneous increase in penetration per time together with extended bit life should result in increased productivity and reduced bit costs.

Jan 1, 1987

By Stephen E. Mosher, Suzanne D. Smith

Ground, air, and water vehicles can expose humans to substantial multi-axis vibration. Multiple input/multiple output relationships or models exist for estimating frequency response functions of linear systems1, 2. These relationships have been applied by some investigators to evaluate the effects of occupied seat vibration3, 4. Using a multiple input/single output model, this study investigated the effects of single- and combined-axis vibration in the fore-and-aft (X), lateral (Y), and vertical (Z) directions on vibration transmission to the human chest. Frequency response functions (transmissibilities) were estimated and compared for the back-on and back-off postures. Methods A rigid seat with seat back was mounted onto the Six Degree-of-Freedom Motion Simulator (SIXMODE). A flat acceleration vibration signal was generated between 2 and 40 Hz at 1.0 ms-2 rms in the single and combined X, Y, Z, XY, XZ, YZ, and XYZ axes. The signals were shifted in time so that the combined inputs were not fully correlated. Lightweight triaxial accelerometers were used to measure accelerations at the seat base (input) and at the bony manubrium of the chest (output). The maximum of nine frequency response functions (H(?)) or transmissibilities were estimated from the auto- and cross-spectra. The system transfer matrix for the XYZ inputs and chest Z output is [ ] where PxZ, PyZ, and PzZ are the cross-spectra between the three inputs at the seat base and the Z output at the chest, respectively, and Pxx, Pxy,…zz are the auto- and cross-spectra between the input signals (? not shown in Eq. 1). Equation 1 can be similarly written for the chest X and Y outputs. Matlab® was used to estimate the auto- and cross-spectral densities for calculating the transmissibilities, ordinary coherences (for single inputs), partial coherences, and multiple coherences. Results Figure 1 illustrates the major chest transmissibilities observed for the two postures. Vertical vibration showed a consistent influence on the chest X response (Chest X/Z), most likely causing chest pitch. Some chest Z responses were observed with X-axis inputs, but the results were variable and difficult to interpret. In general, other factors besides the known inputs did not affect the transmissibilities shown in Figure 1 (Repeated Measures ANOVA, P<0.05). This was

Jan 6, 2006

[nder &apos; 1Oclific?atic>n 1 l&apos;, of Cant r Ict No. S012?U7 , the T1. S. l urc ,:i.11 of Miries ontracted tivit.l &apos;1 -l:eudurn? Barry t1rirl ,~:>:&apos;nci.11c:, for the 1>crfcocrnancu of a afet, Analynin Q::tc n Study to develop a plan for thc organiration nrld opera¬ion of a &apos;Lur(&apos;an ,`,afutj i ily ;i Cn11tur, r Before the con)y)lctic>n of the stucly, the Abiretu.l ustaldish d such a center, the WniL1, and Safety i?&apos;\naly:-.in Cnmtor (l1S;&apos;J:), under the dirucHan of fly, Assistant Director of JTc&apos;"?ltl) 11111 .itut~ 1O1- &apos;l (.. -11: &apos;C&apos;a) :_&apos;-, ?&apos;( )&apos;t. 11. ~.C is 11 c&apos; iC1cnlC:rtc:rr&apos;d at the 1)crnv(jr Federal Center, 1)u:r&apos;,L C,r_i1f,U, rK.]

Jan 1, 1972

By Oliver C. Ralston, Dorsey A. Lyon

Volatilization in retorts has been, until recently, the only commercial process of producing spelter, hence the zinc mine operators have had to meet the terms of the zinc smelters in regard to the following requirements: (1) Minimum percentage of zinc the ore must contain; (2) the chemical combination of the zinc in the ore; (3) the proportion present of those elements that interfere with the suceessful recovery of the zinc when the ore is retorted. In consequence of these requirements, only a comparatively small proportion of the zinc ores mined can be shipped directly to the smelters.

Jan 1, 1919

By P. B. Ritter

The feasibility of redesigning and adapting the all- secondary-explosive, low-voltage, electric safe detonator for use as a delay detonator has been demonstrated. Experimental results have shown that operational characteristics can be adjusted to allow direct competition of safe delay detonators with commercial delay blasting caps. Five different experimental delay period models have been developed and tested. Test results are given and results are evaluated. Subsequent simplified and improved designs for practical and economical mass production are described. Design concepts to meet Bureau of Mines voltage withstand, incendivity, and spark sensitivity requirements are included. Recommendations are made for experimental procedures to ready the safe delay detonator for mass production and extensive use in mining and other industries.

Jan 1, 1977

By Terry R. Neumann

In 1989, the Bureau of Mines conducted a mineral resource investigation of the 52,350-acre Jersey Jack study area, located in the Clearwater Mountains of north-central Idaho. Twenty-eight mines and prospects were examined, and 483 rock, placer, and petrographic samples were collected during the field study. Two properties contain gold resources; mining company data show the Robinson Dike mine contains an estimated 940,000 tons of "drill proven and probable reserves" averaging 0.041 oz/ton gold, and the Bureau of Mines investigation showed the Blacksand placer mine contains an estimated 64,000 cubic yards of identified placer resources averaging $8.13 in gold per cubic yard. Sample analyses from other properties indicate that gold resources are likely to exist; however the low tonnage, narrow, fissure-vein type deposits would require mining by relatively high-cost underground methods and would be subeconomic at a gold price of $400/oz.

Jan 1, 1991

By B. V. Johnson

The Federal Bureau of Mines has conducted research in support of the National Aeronautical and Space Administration&apos;s (NASA) Apollo program to acquire fundamental scientific and engineering knowledge of lunar-mineral resources for NASA&apos;s Office of Advanced Research and Technology. Equipment and techniques were developed to conduct soil shear tests in a simulated lunar environment. Shear tests performed with this equipment in ultrahigh vacuum and controlled laboratory atmosphere showed that simulated lunar soil increased in strength in the simulated lunar environment.

Jan 1, 1973

By Danton L. Paulson

Elevated temperature electrical resistivity measurements were made by the Bureau of Mines on arc-melted, spin-cast, and hot-pressed columbium carbide¬carbon (CbC-C) and zirconium carbide-carbon (ZrC-C) materials up to 2,000° C. The CbC-C materials displayed electrical resistivity values ranging from 35.20 microhm cm at 23° C for hot-pressed material containing 12 wt pct carbon to 242.64 microhm cm at 1,622° C for arc-cast material containing 17.0 wt pct carbon. Electrical resistivity values ranged from 29 microhm cm at 20° C for arc-cast ZrC-C containing 16 wt pct carbon to 279 microhm cm at 1,951° C for hot-pressed ZrC-C containing 21 wt pct carbon. Data from a previous report were included to establish comparison between the electrical resistivities of the CbC-C, ZrC-C, and HfC-C systems.

Jan 1, 1969

By John Wilson

This report describes the performance of Phase I of a project to design, analyze, and demonstrate a multilift longwall mining method applicable to mining coal seams twelve (12) feet or more in thickness. A non-simultaneous multilift operation is the most viable thick seam mining technique for introduction to the United States coal industry. In the case of the proposed site at Emery, Utah it will result in an increase in coal extraction from 30% with present methods to at least 50% and possibly more. The major technological advance involved in this project is mining a lower lift under a previously mined upper lift. To accomplish this, entries must be developed and maintained beneath the upper lift gob. This will necessitate the use of steel supports at frequent intervals throughout the lower lift&apos; entry system. This has not been done in the U.S. to date. An economic analysis of the project indicates that, while this method will result in a higher than average cost per ton for coal mined, the coal would be competitive with current-operation in the area.

Jan 1, 1976