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By Robert E. Barieau

General expressions for evaluating practically all the thermodynamic properties of a fluid from a single equation of state are derived. Most of the formulas are expressed in terms of the compressibility factor, with this factor being an explicit function of the temperature and the molal density. Similar expressions are given using reduced variables.

Jan 1, 1967

By L. Mark Irwin, R. A. Marsyla

The objective of this laboratory investigation was to develop a mattesmelting process for the recovery of copper from industrial smelter dusts . Experimentation was conducted on three samples of Cottrell precipitator dust from a northern Michigan smelter with variations in the following conditions : Temperature , charge composition , pelletization , and moisture content . Based on chemical analyses of the furnace slags , poorest recovery of copper was effected in smelting dry charges regardless of composition . Some improvement was noted with uniformly moistened charges and still more with pelletized (but dry) mixes , but best results were obtained from smelting moist , self - fluxing pellets . Under favorable conditions , experiments yielded furnace slags with an average copper content of only 0.15 percent , which is well below that of industrial copper reverberatory slags .

Jan 1, 1963

By G. S. Scott, G. W. Jones

Trichloroethylene (CHC1CC12) is an important solvent for fats , resins , bitumens, rubber , sulfur , and phosphorus . It is used extensively in drycleaning because of its low order of combustibility and has recently been proposed as an inhalation anaesthetic . Its physical properties have been described by Carlisle and Levine . It is usually considered a noninflammable material ; however , substances that are noninflammable when mixed with air are not necessarily noninflammable when mixed with oxygen . Thus , Hewer's statement that " Trichloroethylene*** is not inflammable under any circumstances , nor will its vapor explode when mixed in any proportion with air , oxygen, or nitrous oxide , " requires qualification , especially in anesthesia, where pure oxygen may at times be substituted for air , This report gives the results of tests made to determine the inflammability of trichloroethylene in various mixtures of oxygen and nitrogen . The trichloroethylene used was Eastman's No. 1300. The boiling point was given as 86 ° to 87 °C . The specific gravity and refractive index of the sample measured in this laboratory were , respectively, 1.45 and 1.4759 at 25 °C .

Nov 1, 1942

By J. W. Horne, W. L. Finley, A. D. Bauer, D. W. Gould

"The Bureau of Mines and the State of Colorado are cooperating in an investigation of the oil shales of Colorado. in this report the yields and the results of analyses of the oil and, gas produced from a number of oil-shale samples from the principal deposits of Colorado and other oil-shale States, are compared with samples from Scotland and Australia, where the oil-shale industry has had its greatest commercial development, and also with a sample from Brazil *here extensive oil-shale deposits are found shale samples were not selected as being representative of the different deposits, but they illustrate the wide variation in the nature of the organic matter of different oil shales.A further study is being made of the chemical composition of the shale, distribution of nitrogen and sulphur. in the products, temperatures at which organic matter decomposes, and the results will be presented in subsequent Papers, With complete data available on the chemical composition of the shales, it may be possible to explain some of the differences in the nature of the products from the various shales,Most of the work described herein was done under the supervision of M. J. Gavin. L. C. Karrick, formerly of .the Boulder laboratory, assisted in the work and gave many valuable suggestions."

May 1, 1924

By M. C. Irani, Maurice Deul, M. G. Zabetakis, T. G. Bobick

This survey was conducted to determine the magnitude of the methane emission and control problem in U.S. bituminous coal mines. The resultant data indicate that the emission rate for any given coalbed depends primarily on the coal production rate and on mine depth, as well as on the nature of the coalbed and the surrounding strata. An excellent correlation was found between (1) the methane emission rate and (2) the product of coal production rate and mine depth for the mines in the Pittsburgh, Pocahontas Nos. 3 and 4, and the Illinois Nos. 5 and 6 coalbeds. The highest total emission rates found in U.S. bituminous coal mines were as follows, in million cubic feet per day: Monongalia County, W. Va., 39; Marion County, W. Va., 30.4; McDowell County, W. Va., 13.1; Washington County, Pa., 11.9; Greene County, Pa., 11.4; Buchanan County, Va., 21.6; Jefferson County, Ala., 10.3; and Franklin County, Ill., 6.6.

Jan 1, 1972

By Fei Chen, Lesley J. Gaydos, Laurence M. Demers, Douglas C. Kuhn

The fibrogenic effects of silica in experimental animals and humans has been extensively studied (I 7, 20). However, the pathogenesis and molecular mechanisms underlying lung injury and fibrosis resulting from silica exposure remain to be elucidated. It is well-documented that silica can stimulate monocyte-macrophage lineage cells to produce cytokines and growth factors, including interleukin-I (IL- I) (20), tumor necrosis factor-ex (TNF-cx) (I 7), insulin-like growth factor-I (IGF-1) (4), and transforming growth factor-P (TGF-P) (24). Consequently, it has been suggested that the fibrogenic effect of silica may be mediated by cytokines in the fater stages of silicosis. During the early phase of interaction between silica and the pulmonary alveolar macrophage, several direct and indirect lines of evidence suggest that reactive oxygen intermediates (ROI) may play a pivotal role in silica- induced tissue damage (2I, 22). One of the most important components of and contributors to ROI is nitric oxide (NO) produced from L-arginine and molecular oxygen under the catalytic influence of NO synthase (NOS) (I 9). At present, at least three NOS genes have been cloned: a constitutive neuron NOS, a constitutive endothelial cell NOS and an inducible NOS (iNOS) (16). A number of factors have been shown to differentially induce iNOS gene expression in different cell lines including bacterial cell products and foreign antigens. During inflammation, NO is a double-edged sword in terms of the host immune defense mechanisms and the physiologic response to an inflammatory insult. The macrophage is one of the major cellular sources of NO. During the early phase of acute inflammation, NO produced from the macrophage appears to facilitate the clearance of pathogens and promotes a local relaxation effect on the microcirculation of vascular smooth muscle. When the production of NO is left unattenuated, especially under oxidative stress, direct cytotoxic effects of NO can emerge through the formation of peroxynitrite as a result of a reaction between NO and superoxide (2).

Jan 1, 1998

By W. E. Wallace, P. Bolsaltis, M. J. Keane, B. L. Rauaboni

Thermal treatment of respirable size silica dust samples results in marked changes in their hemolytic activity. These changes can be correlated with changes in the characteristics of the particle surface as measured by infrared spectra, zeta potentials, and specific surface area. Silica samples from various sources (Min-U-Sil, fumed silica, and a NIOSH standard sample) were heated or calcined at temperatures ranging from 100-1095C. The hemolytic activity of the crystalline materials decreased after thermal treatment. The behavior of the fumed material was found to be more complex. Material of very large surface area (small particle size) exhibits an initial increase in hemolytic activity upon calcination. This result confirms other experimental observations pointing to a particle size of maximum toxicity. Tre changes in hemolytic activity can be related to infrared spectra and zeta potentials of the materials. The absorption band in the 3200-4000 cm-1 frequency region of the fumed material disappears upon heat treatment while a sharp, characteristic band at 3750 cm-1 increases in intensity. Zeta potential measurements conducted in the pH range of 2.0-10.5 exhibit a unique change in zeta potential v.s. pH profile with heat treatment. These findings indicate that the removal of active surface silanol groups by calcination results in reduced cytotoxicity, as measured by a hemolysis test.

Jan 1, 1988

By David C. Oyler

Three long horizontal holes were drilled from a directionally drilled surface hole at the Emerald Mine near Waynesburg, Pa. The purpose was to adapt the technique of directional drilling for use in draining methane from coalbeds. A 504-m (1,652-ft) long, 76-mm (3-in) diameter, circular arc pilot hole was drilled, using a downhole mud motor, to enter the Pittsburgh coalbed at a vertical depth of 305 m (1,000 ft). The hole was reamed to 222 mm (8-3/4 in) and was cased to a measured depth of 486 m (1,595 ft). Three 76-mm (3-in) diameter horizontal drainage holes were then drilled, totaling 2,909 m (9,544 ft) of horizontal hole. Improvements in drilling methods increased the average drilling rate from 20.4 ill (67 ft) to 64.9 m (213 ft) per day. The cost of drilling the directional and horizontal holes (using a Government-owned drill rig) was $1,169,530, a figure inflated by inexperience and by delays caused by lost-circulation problems and fishing operations. An estimated total drilling cost of $960,000 (including rental of a drill rig) for an improved system, was determined by a detailed cost analysis. Initial gas and water production from November 1979 through May 1980 was low because of caving of the horizontal holes drilled in shale near the bottom of the casing.

Jan 1, 1982

SCOPE AND APPLICATION The rules cover the installation and use of electrical equipment in coal mines.- For generating stations, substations, lines, and equip¬ment aboveground, reference is made to existing rules covering such locations, viz, the National Electrical Code and the National Electrical Safety Code and any existing State or municipal regulations. The purpose of the rules is to set forth methods for safe electrical installation. In preparing the rules five basic measures for safe¬guarding the use of electricity in mines have been followed, viz 1. Remove the contributory causes of accidents or danger. 2. Remove from the vicinity of electrical apparatus all elements susceptible to the influence of electricity. 3. Keep the electric current where it belongs, if possible; if not, limit the area of its activity by protective devices. 4. Use a. large factor of safety in the selection, installation, and in¬ spection of equipment. 5. Have full control of the operation of electrically driven machines. Each rule that is given is proposed as necessary or helpful to the accomplishment of one or more of these measures. DEFINITIONS OF TERMS USED Alive.-See definition of " live." Approved.-The term " approved " means accepted as suitable by a competent committee, board, or organization designated by those adopting the rules. Authorized person.-The term " authorized person " means a per¬son appointed or permitted by the official designated by the State mining laws as the one in charge of the operation of the mine to carry out certain duties incident to the generation, transformation, and distribution or use of electric energy in the mine, such person be-

Jan 1, 1926

By B. J. Scheiner

Extraction of silver from silver mill tailings by an electrolytic oxidation procedure was investigated by the Bureau of Mines. Various parameters affecting silver extraction, such as electrolysis time, particle size, and dissolution of the silver as the tetrachloro or cyanide complex, were studied at 30° C with an electrolyte concentration of 20 weight-percent sodium chloride. Resulting silver extractions ranged from 77 to 90 percent, depending on the tailings being treated. Concomitant extraction of mercury ranged between 90 and 95 percent. Power consumption was 52 to 90 kilowatt-hours per ton for the tailings investigated. Comparative experiments using direct cyanidation resulted in extraction of 46 to 82 percent of the silver and 20 percent of the mercury. Cyanide consumption ranged from 3.3 to 9.4 pounds per ton of tailings, depending on the tailings being treated. Silver and mercury were recovered from leach solutions by precipitation on iron powder, followed by conventional distillation and fire refining steps.

Jan 1, 1972

By T. W. Johnson

The Bureau of Mines, in cooperation with the Natural Gas Department of the American Gas Association, has in progress a study or the flow of natural gas through high-pressure transmission lines. A major problem of this study is to compare the deliveries calculated from the gas pipe-line flow formulas commonly used, with the metered deliveries from pipe lines in operation. In order to obtain such comparisons a series of tests has bean made on 25 operating pipe lines in Kansas, Oklahoma, Louisiana, Arkansas, Texas, and California ACKNOWLEDGEMENTS Study of the flow of natural gas through high-pressure transmission lines was made under the general supervision of H. H. Hill, former chief petroleum engineer of the Bureau of. Mines, H. C. Fowler, acting chief petroleum engineer of the Bureau of Mines, N. A. C. Smith, superintendent of the Bureau of Mines Petroleum Experiment Station at Bartlesville, Okla., and T. Brandenthaler, chief of the oil and gas action of the Bartlesville station.

Jan 1, 1929

By J. C. LaScola

Development of methanometers and anemometers for underground use in coal mines is reviewed. The first semicontinuous recording methanometer was developed in 1961 in West Germany. The Bureau of Mines developed an instrument using; pellesters that was a continuous recording methanometer. Expansion of freon gas created a vacuum which pulled the methane-air mixture through a tube to an electrically heated, catalyst-impregnated pellester where the mixture was burned. The National Coal Board of England developed a continuous recording methanometer based on the principle of the Davy flame safety lamp. A thermo-pile was used to sense the hurt output of the flame. Finally the Bureau of Mines improved its methanometer by eliminating the freon gas and using a diffuser head to a monitor methane-air mixtures. Development of recording anemometers proceeded from the use of a photo¬cell and light source to sense rotation of the Biram-type anemometer blades to the use of a Hall detector to sense, rotation by measurement of electromagnetic pulses.

Jan 1, 1969

By Earl W. Waay

"Since the beginning of the petroleum industry in 1839, up to within two or three years ago, these has been a dearch of engineers who have had the fundamental technical training also sufficient practical experience so that they could compete with practical men. Need for Technical Investigations in Industry: As in the early stages of the mining industry, the petroleum industry has been rather slow in realizing the need for technical assistance and investigators in the development and production of oil lands. The rapid increase in consumption, however, during the past few years has accentuated this need more than anything else could have done. When it is realized that our production cannot longer keep pace with the demand, it is easily understood why it is imperative that be instituted which will tend to conserve and prolong the supply of oil from the fields now known. It is interesting to note from preliminary production figure given cut by the U. S. Geological Survey, for the year 1919, that the United States produced about 430,000,000 barrels, an increase of 22,000,000 or 6 per cent over 1918 production and also there was imported, chiefly from Mexico, a little over 52,000,000 barrels, making a total of 430,000,000 barrels, to satisfy the trade demand in the United States of which almost 6,000,000 barrels was exported. Stocks were not materially increased.Other significant facts regarding our petroleum industry, are that just recently the U. S. Shipping Board in soliciting bids for 24,000,000 barrels of fad oil to meet prospective needs, received bids for only 1,500,000 barrels at prizes ranging from 75 to 90 per cent higher than was paid last year. One large company on the Pacific Coast has stopped its export trade, and has notified consumers,of gas-engine distillate that they will no longer make deliveries of this product. This will materially affect the farmer, in many instances, through his use of the truck and tractor."

Apr 1, 1920

By A. F. Colombo, D. W. Frommer

Bench- scale tests were made to determine the applicability of flotation as a means of upgrading finished and semifinished magnetic concentrates prepared from reductively roasted iron ores . Both anionic and cationic flotation methods were used to remove siliceous gangue from the magnetic concentrates and produce upgraded products . Seven magnetic concentrates , containing from 6.7 to 13.7 percent SiO2 , were improved by the flotation treatment , yielding final concentrates containing less than 6.0 percent Si02 . Cationic flotation methods were studied on four of the seven samples ; of this group only one sample yielded better results by cationic flotation than by the anionic method .

Jan 1, 1964

By Ted C. Briggs

Twenty-two compressibility runs were made with helium over the temperature range -5° to 80° C and at pressures to 800 atmospheres. A Burnett apparatus was used. Data from the runs were fitted to a fourth degree polynomial equation of state in the pressure and a weighting factor of Pr-3/4 was used. All data for a particular isotherm were treated simultaneously. A temperature function was found to represent the parameters B and C. Compressibility factors determined by this investigation are believed to be accurate to better than 0.05 percent.

Jan 1, 1970

By H. W. St. Clair

In about 1930, Degussa applied for a patent on a process for the of oxides, carbides, sulfides, and other nonmetallic impurities by filtration in the molter state. The filtering media listed were wire screen, coke, and ceramic materials, and quartz. It was also suggested that filtration might be combined with chemical reaction between the metal and the filter medium or that might be added to the system. No patent was granted on the general scheme, but several years later a patent was granted on a continuous process purification of crude light metals, especially or alkali earth and their alloys. The melt was stirred at 1 temperature at which the impurities (such as oxides and salts) remained solid and the metal was drawn through a filter tube. The impurities collected under the filter and were removed by a screw conveyor. Crude sodium was purified by this process in Degussa's Knapsack plant. During the last war, when the refining of scrap became a very urgent Problem in Germany, experimental investigations were extended to separation of other metals and metallic compounds by filtration. Preliminary experiments seemed to confirm the opinion of Dr. L. Weiss that the principles of wet chemical filtration might be applied to a great extent in the purification of metal and alloys.

Jan 1, 1949

Various aspects of judgment and decision-making are key themes in this book. The model presented here serves as a loose structure for the chapters that follow this one. The notion of a model is introduced because growing research interest in the subjective aspects of group and individual behavior has led to a debate over whether judgment is a skill that can be understood scientifically. A related point of contention is whether such an understanding could lead to the development of methods for estimating people's ability to make good decisions during an emergency. There is some literature that supports the potential usefulness of this approach. However, little agreement seems to have been reached on how to define and operationalize even those basic concepts necessary to assess the soundness of decisions from within their environmental and group contexts [Jensen and Benel 1977; Godden and Baddeley 1979; Baumann and Bourbonnais 1982; Brecke 1982; Stone et al. 1985]. A look at the real-world process is clearly needed. The need to attempt a better understanding of judgment and decision-making properties stems from those occasions in the existence of an organization when there is a lot at stake. The process of decision-making (which is part of the exercise of judgment) has been analyzed in situations such as corporate takeovers [Janis and Mann1977], military combat [Begland1979], clinical emergencies [Baumann and Bourbonnais 1982], and aviation events [Billings and Reynard1984]. The fundamental assumption of these analyses is that, while there are untold successes, there are also notable numbers of failures resulting from decisions that can be ascribed to one or more errors in judgment. From a cognitive perspective, any person engaged in decision-making (either alone or in a group) is actively involved in a process characterized by certain elements. These were mentioned in chapter 1, but are reiterated briefly at this point: (1) detection of a problem, (2) definition or diagnosis, (3) consideration of available options, (4) choice of what is perceived as the best option given recognized needs, and (5) execution of the choice based on what has transpired [Flathers et al. 1982; Baumann and Bourbonnais 1982]. At any moment in this process, there are factors at play that have a large impact on one's ability to solve complex problems in a limited time: (1) an internal state [Hedge and Lawson 1979] is the sum of a person's psychomotor skills, knowledge, attitudes, etc.; (2) uncertainty [Brecke 1982] is caused by faulty or incomplete information received from the external environment; (3) stress [Biggs 1968; Jensen and Benel 1977] is generated both by the problem at hand and any background problem that may exist; and (4) complexity, as it is used here, refers to the number of elements involved that must be attended to. These variables are depicted in figure 5.1, and their relationship to each other and to an outcome is indicated. This schema is designed to suggest interaction, because while the judgment and decision-making process may be conceptualized as discrete stages, experience tells us that this is not the way people function in real-world situations.

Jan 1, 2000

By G. R. Hopkins, E. W. COCHRANE

According to reports received by the United States Bureau of Mines , Department of Commerce , as of January 1 , 1930 , there were 412 completed refineries in the United States with a daily crude oil capacity of 3,755,585 barrels . This compares with 413 refineries of 3,509,540 barrels capacity on January 1 , 1929 , which indicates that whereas the number of refineries was practically unchanged , the total capacity increased 8 per cent during the past year . Of the completed plants as of January 1 , 1930 , 358 plants , of 3,634,825 barrels total capacity , were operating and 54 , with a capacity of 130,760 barrels , were shut down . Compared with a year ago , this indicates a decline in the percentage of the total refinery capacity that is inoperative . There has been a decided decrease in the number of shut-down plants since 1924 and 1925 , when one plant in every three was inoperative . Many of the inoperative plants of 1924 and 1925 were constructed soon after the boom times of 1920. Some of these were operated for a time but were unable to show a profit during 1923 and 1924 , when an overproduction of crude petroleum was accompanied by demoralized markets for refined products . Prices for refined products improved in 1925 and 1926 , but only a comparatively few of the shut -down plants , then partly obsolete , were able to obtain or renew their crude connections and compete successfully with the larger , more firmly established refineries . After five years or more of continuous idleness , a refinery would be rendered practically useless through corrosion and obsolescence . Consequently , most plants now being carried as " shut -down " have operated intermittently since 1923 . struction . A material change occurred in 1929 in the matter of plants under con- On January 1 , 1929 , there were 14 plants under construction , with a potential capacity of 99,000 barrels per day , whereas on January 1 , 1930 , there were only eight plants of 37,200 barrels capacity being built . This decline was due to the fact that the construction program in west Texas , which was at or near its height on January 1 , 1929 , was completed prior to January 1 , 1930 .

Apr 1, 1930

By G. R. Palmer

Preliminary studies by the Bureau of Mines were conducted to determine the feasibility of a multiple-compartment, ion-exchange (MCIX) column simulator for examining the effect of multiple-orifice plates in the column. A rectangular, five-orifice, three-compartment, MCIX simulator with a cross-sectional plate area of 0.66 ft2 was used for the investigation. Orifices with open areas of 1, 3, and 5 percent were used with various operating conditions. The study was separated into three separate sections: (1) solution flow effect, (2) fluidization effect, and (3) resin transfer effect. The solution flow and fluidization studies showed that for solution flow rates of about 3 gpm/ft2, a I-percent open area plate functioned best, while at solution flow rates of 9 and 15 gpm/ft2, the best open areas were 3 and 5 percent, respectively.

Jan 1, 1981

By J. K. Whyatt

Researchers at the U.S. Bureau of Mines have been exploring recent advances in the use of strain-softening constitutive laws that approximate shear fracturing. The purpose of these tests is to investigate shear-fracture-related rock bursts in hard-rock mines. The capabilities and remaining problems in the use of strain-softening laws in finite-element, distinct-element, and finite-difference methods are reviewed. Performance of the finite-difference implementation of strain softening is compared to classic experimental results and observations of rock mass behavior in the Coeur d'Alene Mining District of northern Idaho. The results show promise for developing methods to identify the general location and orientation of shear fractures and their sequence of occurrence, but such methods cannot be relied upon to quantify post-fracture loads or displacements accurately. Uncertainty over the amount of energy consumed by failing rock and the dependency of energy consumption on model mesh definition prevent direct application of the results to analyses of rock bursts.

Jan 1, 2010