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By N. S. Dalal, X. Shi

It has been known for more than a decade that vanadium (V) stimulates the oxidation of NADH by plasma membranes (1) but the underlying mechanism is still not fully understood. This effect has been attributed to a membrane-associated NADH-dependent vanadium (V) oxidoreductase (1). Subsequent studies suggest that vanadium ( V) can accept an electron from fiavoprotein dehydrogenase that oxidizes NADH (2). The phenomenon ofNAD(P)H oxidation coupled to vanadium(V) reduction has also been demonstrated in other biological systems (3-6). A recent electron spin resonance (ESR) study from our laboratory reported on the accumulation of vanadium (IV) duringthe reduction ofvanadate (vanadium(V)) by the ftavoenzymes glutathione reductase (GSSG-R),4 lipoyl dehydrogenase, and ferredoxin-NADP+ oxidoreductase in the presence of NAD(P)H (7). It was concluded therein (7) that these ftavoenzymes function as NAD(P)H-dependent vanadium(V) reductases. More recently, however, Liochev and Fridovich (8) have argued that the ESR data (7) do not demonstrate that the investigated fiavoenzymes act as vanadate reductases. They suggest an alternative mechanism in which the fiavoenzyme simply serves as a generator ofsuperoxide (02) radical, which acts as a propagator of the radical chain reaction leading to NAD(P)H oxidation (9, 10), as summarized below:

Nov 1, 1995

By L. L. Oden

The U.S. Bureau of Mines and the Department of Energy (DOE), through its contractor EG&G Idaho Inc., are collaborating on a multiyear research project to evaluate the applicability of three-phase, electric arc furnace melting technology to vitrify materials simulating low-level radioactive and mixed wastes buried or stored at the Idaho National Engineering Laboratory and other DOE sites. The melter is a sealed, 1-t (1.1-st), three-phase, 800-kV?A electric arc melting furnace with 10.2-cm-(4-in?) diameter graphite electrodes, water-cooled roof and sidewalls, and four water-cooled feed tubes. A water-cooled copper fixture provides for continuous tapping of slag. An instrumented air pollution control system (APCS) with access ports for analysis and a feeder based on screw conveyors and a bucket elevator are dedicated to the facility. Test data are provided by an arc furnace analyzer and by sensors indicating feed rate; slag temperature; and temperature, pressure, and velocity in the APCS. These data are received by a data logger, digitized, and transmitted to a personal computer for storage and display. This unique waste treatment facility is available for public and private use on a cost-sharing basis.

Jan 1, 2010

By M. J. Ankeny, J. J. Forbes

"One of the main functions of the U. S. Bureau of Mines, as authorized by Congress, is to investigate safety and health conditions, to disseminate information regarding safe and unsafe practices in mining, and to aid in improving safety and health conditions of mining communities and in promoting the welfare of the miner. Among several methods of reaching the miner and interesting him in safety work, perhaps the most effective is through the 11 mine safety stations and 11 railroad cars known as mine rescue, or more correctly, mine safety cars.Frequently, the Bureau of Mines receives requests for information regarding the purpose, equipment, personnel, and construction of its safety cars used in the field service. It is the intention of this circular to present to the mining public in particular, and to the public in general, some definite information regarding these safety cars and their functions.The cars are operated throughout the mining fields of the United States and are headquartered as follows (see fig. 1): Car 1, Reno, Nev.; Car 2, Raton, N. M.; Car 3, Pittsburgh, Pa.; Car 4, Terre Haute, Ind.; Car 5, Pineville, Ky.; Car 6, Pittsburg, Kans.; Car 7, Huntington, W. Va.; Car 8, Duluth, Minn.; Car 9, Butte, Mont.; Car 10, Des Moines, Iowa; Car 11, Anchorage, Alaska.One of the most important purposes of the U. S. Bureau of Mines safety cars is to render service at mine fires and explosions where human life is endangered. State mine inspectors and other interested persons are supplied with itineraries of the car operating in their districts from time to time, so that they may know at all times where the car can be found in case of emergency. When these disasters occur the car may be reached direct or through its field headquarters, and upon receiving word of a mine disaster, or request for assistance, it immediately proceeds to the scene of trouble. Frequently a special locomotive is supplied by the railroads and in many instances the movement of the car is given the right of way over all other railway traffic. Upon reaching the destination, the facilities and personnel of the car are immediately available for rescue and recovery operations.Following most mine disasters a thorough investigation is made by engineers of the Bureau of Mines, and a confidential report is submitted to the operator. The information gained in this manner from a large number of mine fires and explosions, together with the knowledge gained from the experimental work carried on at the Experimental mine of the bureau at Bruceton, Pa., serves as a basis upon which the bureau is able to recommend preventive measures whereby similar occurrences may be averted. The bureau car is often used as headquarters for the investigating engineer when such an examination is being made."

Mar 1, 1931

By J. V. Scalera

Because of U.S. dependency on imported critical metals, the Bureau of Mines has conducted research to evaluate the possible substitution of nitrided low-alloy steels for higher chromium-containing alloys. The corrosion data for nitrided steels are limited primarily to the Soviet literature. The objective of this study was to determine the corrosion properties of six commercially nitrided low-alloy steels in a 5-wt % NaCl solution at pH 4. Weight-loss tests indicated that, in deaerated test solutions, most of the nitrided steels were less corrosion resist-ant than nontreated steels. However, electrochemical tests indicated that under more oxidizing conditions, nitrided materials are converted to a passive state with a significantly reduced corrosion rate. Elec-trochemical tests performed in an aerated environment confirmed the passivity of the samples in an oxidizing environment.

Jan 1, 1984

By Spencer P. Hwell, Charles E. Munroe

"Among the surplus explosives left on band with the War Department was a quantity of that styled Trojan Grenade Powder, which was especially designed during the war for use as a bursting charge in grenades and for which naturally there would be very little military use in time of peace. With a view to its disposal through use in civil projects a quantity was sent to the Bureau of Minas explosives experiment station, where analysis showed that its characteristic explosive ingredient was nitrostarcn and that the powder bad the following composition:Trojan Grenade Powder appears as a dark gray granular substance, part of which is slightly pulverulent. The granules fairly hard. The explosive is not at all dusty, and has the consistency of granulated sugar.Nitrostarch is a substance produced by treating starch with nitric and sulphuric acids and in appearance it looks very little different from powdered starch. It resembles nitrocellulose and nitroglycerin in its constitution and explosive properties and has been longer known than either, it having been prepared by Braconnet in 1833. Nitrostarch explosives have in recent years been developed for industrial use in this country, they having been used to an extent in blasting in the Canal Zone, yet as this grenade powder was a special composition it seemed desirable that a complete series of tests should be run upon it. This was done, and the results are reported in the following table in comparison with those previously obtained in testing ammonia dynamite."

Jun 1, 1920

By Oliver Bowles

From the most remote periods of civilization stone has been used to perpetuate the memory of individuals or to immortalize their noble achievements. Ancient memorials ranged from simple piles of stone (cairns), or single markers, to great obelisks and pyramids or magnificent mausoleums. The Taj Mahal at Agra, India, built of white marble by Shah Jehan in memory of the Empress Mumtaz Mahal, is one of the most beautiful and costly memorials ever built. It was erected between 1632 and 1650 at an estimated cost of $50,000,000 or more and is today an object of unusual interest for travelers. Other magnificent memorials both ancient and modern are to be found in many lands. No sharp line can be drawn between buildings and monuments, because the larger types of memorials such as the Bok Singing Tower, Lincoln and Jefferson Memorials, and mausoleums of various types have features in common with buildings. However, great care must be exercised in selecting a site for a quarry that will produce acceptable monumental stone because appearance as well as quality is of prime importance. The deposit must be of uniform texture and attractive color and must be notably free of knots, hairlines, impurities, incipient seams, or other defects. Many memorials are of polished stone, and spots or streaks that might be virtually Invisible on a natural rock face will appear distinctly on a polished surface. Hence, stone to be polished must be selected with unusual care. However, less flawless stone may be used for hammered surfaces.

Jan 1, 1955

By George S. Rice

A novel method of extinguishing a mine fire in a stowed or gob-filled area by employing liquid carbon dioxide under high pressure eras used recently with success at the President (Prasident) coal mine, Bochum, Germany, as reported by P. Cabolet in Gluckauf (Apr. 24, 1937, p. 393) The use of carbon dioxide gas as a fire-fighting agent in surface plants and in ships is now general practice in the United. States, but when it has been tried for extinguishing fires in mines in large areas more or less confined by stoppings it has not been successful. Examples of the latter method of attempting to fight mine fires are given in Bureau of Mines Bulletin 229, Fifty-Nine Coal-Mine Fires; How They Were Fought and That They Teach, by G. S. Rice, J. VT. Paul, and 14. VT. von Bernewitz (1927). The reason for its nonsuccess may be either that the stoppings are not tight or that the roof and pillars are more or less fissured and enough air passes into the area to sustain a slow fire, whether of spontaneous origin or produced by gas explosion or other source of ignition.

Jan 1, 1937

By A. B. Hooker

Investigations at the Pittsburgh Experiment Station of the Bureau of Mines have shown that satisfactory operation of a flame safety lamp depends not only upon proper design and assembly of the lamp but also upon the kind

Jan 1, 1945

By L. Mallett

The changing demographics of the mining industry make successful passing of knowledge and skills to the next generation critical. Training methods and technologies are being developed to meet this need. Twenty years ago classroom training was largely a one-way transfer of knowledge through instructor lectures. In contrast, instructors today can use virtual reality technologies to guide trainees as they fully participate in learning experiences. Trainees can interact with the virtual work environment, co-workers, and equipment without being exposed to workplace hazards. The speed of advancement in mine safety, health, and production training shows no sign of slowing in the next 20 years. Researchers at the National Institute for Occupational Safety and Health have studied and participated in the evolution of miner training. A look at training materials they have created in the past and those they are currently developing reveals changes in methods and technologies over time and also key characteristics which have remained constant. Possibilities for the future can he discussed in the framework of an implementation of virtual reality in new miner training sessions. The example computer-based training package teaches new miners to read mine maps and provides opportunity to practice navigation skills in a virtual mine. With this 'serious game', trainees experience the look and feel of moving through an underground coal mine while in the safety of their classroom. During field-testing in 2007, trainees and instructors responded very favourably to this new way of learning. The software was usable by mine trainers with even limited computer expertise and could be installed on the affordable computers they were using for their more traditional slide presentations. The Underground Coal Mine Map Reading Training's foundation on past successful development strategies and its acceptance by today's instructors and trainees provide valuable lessons for developing training materials, strategies, and technologies for mining's future.

Jan 1, 2009

By Ralph L. Windrow

This paper is one of a series being prepared for and published by the United States Bureau of Mines describing methods and costs of mining and preparing sand and gravel for market at various plants throughout the United States. These papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent operating expenditures only and not total costs. It is recognized that publication of total costs might in many instances cause embarrassment to individual producers as well as to the industry as a whole. On the other hand, operating costs are essential to the technical discussion and study of the methods employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue. The Clowdy plant, with which this paper deals, is located 7 miles west of Dallas, Tex., and has a rail connection with the Texas and Pacific Railway. In addition to the rail outlet there is a paved road over which materials produced at this plant can be moved into Dallas by truck.

Jan 1, 1932

By R. G. Gürtunca

The future of the United States (US) mining industry will be affected greatly by recent coal mining disasters. These have resulted in new legislation which will have an impact on mining economic costs as well safety and health of miners. This paper discusses the changes that new legislation and regulations are making to the industry and current research that is producing technologies to make mining safer and will likely impact the future of mining.

Jan 1, 2009

By E. D. Gardner

A custom gold and silver plant is one that treats ores for a fee. Usually such plants are located in mining districts and treat local ores. Ores of milling grade generally can stand only moderate transportation charges. These plants are scattered throughout the West. Most plants now doing a custom business originally were built by mining companies to handle ores from their own mires. As excess mill capacity became available ores from neighboring properties were treated, vainly as an accommodation. Later, as their own ore bodies became depleted, the mills were operated entirely on a custom basis. A few plants pull ore from their own mines only when the supply of custom ore is insufficient to keep the mill operating. Some of the present custom plants were built for custom work alone. Although built originally to treat the ores of the Golden Cycle mine, the Golden Cycle plant at Colorado Springs, Colo., soon became a custom mill and has been operating successfully for many years. It is the largest gold mill in the Western States and. treats Cripple Creek ores, from which most of its tonnage still comes. The plant is equipped to treat a great variety of ores and receives shipments from a wide area. It competes with smelters in Colorado, as it has a roasting plant to prepare sulphide concentrates for treatment in its cyanide plant. Most custom mills, however, are not adapted for more than one or two kinds of ore. Gold occurs in its ores both in the metallic state (free) and locked up in sulphides. It also occurs in a few places, notably at Cripple Creek and a few other Colorado districts, as tellurides. Mien the gold occurs in the native state, the ores is said to be free-milling and can be recovered by amalgamation. Usually, however, some subsidiary treatment is required to make a satisfactory extraction. Amalgamation generally was followed by tabling in the earlier mills; at present, flotation has replaced tables at many places. As depth is reached in raining and the workings extend below the oxidized zone the character of the ore usually changes, or, as the miners say, "it gets base". Since the advent of flotation, the average recovery of gold in base ores has been improved-greatly. Cyanidation is applied to some types of both gold and silver ores. The recovery by cyanidation is in general considerably higher than by other methods in vogue and in addition has the advantage of making a finished product which can be sold directly to the mist, thus obviating smelting charges on concentrate and discounts

Jan 1, 1935

By E. J. Matson

"SUMMARYThe Bureau of Mines has been investigating deposits of critical and essential minerals in the United States since 1939. Projects were set up on only the most promising properties. A preliminary examination of the Rio Grande property was made by Bureau of Mines engineers in July 1942 and the property was examined again in July 1943.The Geophysical Branch of the Bureau undertook a Geophysical survey of the area in November 1943 and was intermittently active in the district until June 1946. The major portion of their work was done from June 191 to November 1945. Favorable areas for exploration were recommended by the Geophysical Branch of the Geological Survey, 3/ and all holes were drilled in them.Two projects were set up by the mining branch in an endeavor to find ore bodies on the strength of the geophysical information."

Sep 1, 1947

By Irving Hartmann

The fire end explosion hazard of excessive coal-dust deposits in mines has been recognized for many years, and important measures have been developed for reducing dust formation and to alley loose dust near its source. Nevertheless, in the course of normal mining it has been estimated that 1 to 3 percent (in some thin, friable seams up to 10 percent) of the total coal mined is reduced to dust of through-20-mesh fineness. In highly mechanized, continuous mining operations the production of fines is even greater. Most dust is trapped near its point of origin and removed from the mine, but large quantities are transported by the air current and by haulage into entries, where the greatest proportion settles on the floor and the balance on the rib and roof surfaces. The latter is generally finer in particle size than the floor dust; this, coupled with its more advantageous position for dispersion, makes the rib-roof dust (also to be referred to as overhead dust) a greater potential explosion hazard.

Jan 1, 1954

By Bruce I. Thomas

In 1943, the Bureau of Mines investigated the occurrence of cassiterite in the gravels of Morelock Creek which flows into the Yukon River 32 miles east of the confluence of the Yukon and Tanana Rivers in central Alaska. Samples of the gravels were obtained by churn drilling test pitting, shaft sinking, and open-cut mining. The gravels along Morelock Creek are about 6 feet in depth and covered with about 2-1/2 feet of overburden. The overburden is frozen, but the underlying gravels are not. Cassiterite, with gold and other heavy minerals, is usually concentrated in the first 2 feet of' gravel above bedrock and in some places penetrates into joint planes in the bedrock. The various methods of obtaining samples are discussed, and drill logs and analyses are tabulated in this report.

Jan 1, 1948

By M. G. Pelipetz

High-pressure, high-temperature hydrogenation of coal has been known and practiced for many years. A full' understanding of the mechanism in this process by which coal is converted to oil and gas must rest on a critical interpretation of the manner in which external variables influence the rate and the course of the coal-hydrogenation reactions. Same Bureau of Mines studies on the effect of temperature, catalyst, and rank of coal on these reactions have been published. The effect of pressure was not studied in this earlier work, and the effect of reaction time was complicated by the interruption of long reaction periods in order to refill the autoclave with hydrogen. It is the purpose of this paper to present data from more recent autoclave experiments that extend the results of Storch, et al, on the kinetics of coal hydrogenation. These data must be explained by any comprehensive theory of coal hydrogenation; their detailed evaluation, however, will be deferred until a later publication.

Jan 1, 1949

By L. M. Chan, D. H. Carlson, J. H. Johnson

"This paper discusses the evaluation and application of a portable parked-vehicle tailpipe emissions measurement apparatus (EMA). The EMA consists of an exhaust dilution system and a portable instrument package. The EMA instantaneously dilutes and cools a sample of exhaust with compressed nitrogen or air at a known dilution ratio, thereby presenting it to instruments as it is presented to personnel in the surrounding environment. The operating principles and governing equations of the EMA are presented.A computational method is presented to determine the engine operating and performance parameters from the exhaust CO2 concentrations along with an assumed engine overall volumetric efficiency and brake specific fuel consumption. The parameters determined are fuel / air ratio, mass flow rates of fuel, air and exhaust emissions, and engine brake torque and horsepower. These calculated engine parameters are used to characterize engine load when performing EMA in-field tailpipe sampling without a dynamometer, and to detect deteriorated engines.Evaluations of the EMA by comparison of diesel tailpipe measurements with those made using laboratory-grade instruments showed that the EMA measurements are accurate and reproducible. The results also show that the EMA is capable of detecting emission concentration changes resulting from engine faults. Calculated engine operating and performance parameters correlate and compare well with laboratory-measured values.The EMA in-field engine loading and tailpipe sampling procedures for parked vehicles are presented, and results of the EMA field measurements are also presented. Low coefficients of variation for repeat EMA tailpipe measurements on diesel-powered haulage vehicles in four underground mines indicate that the EMA in-field engine loading and tailpipe sampling procedures are reproducible.An analysis of EMA tailpipe measurements for three haulage vehicles in one mine shows that the EMA can: 1) identify haulage vehicles that emit excessively high pollutant concentrations, and 2) provide data needed to evaluate and determine the efficiency and effectiveness of tailpipe emission control devices.Finally, recommendations for a proposed commercial EMA system are presented. This commercial system would overcome many of the adverse features of the prototype EMA used in these tests."

Mar 1, 1992

By J. F. Barkley

During the present war emergency, under the urge of the Federal Government to store coal, the following; questions are arising n the minds of coal users: (a) Will the coal lose any of its heating value in storage? (b) Will it slack and give a smaller-size coal? (c) Will its burning characteristics change in any way? (d) Will it catch fire from spontaneous combustion? (e) What precautions should be taken when storing coal? In regard to the loss of heating value of coal in storage, tests made by the Bureau of Mines show that the loss commonly has been overestimated. Various types of storage tests were made on New River, Pocahontas, Pittsburgh Gas, and Sheridan Wyoming coals. The following is quoted from Bureau of Mines Bulletin 136, Deterioration in the Heating; Value of Coal During Storage, by H. C. Porter and F. K. Ovitz:

Jan 1, 1942

By D. T. Couillard

Video technology is becoming an important tool for many designers of industrial training programs. This report describes how trainers at the Minntac Mine, Mt. Iron, MN, have developed videocassettes of safe job procedures (SJP's) for training miners assigned to perform unfamiliar work tasks. All steps necessary for videocassette production, from idea to finished product, as well as the required equipment and prices, are listed and/or briefly explained. Minntac officials believe that the SJP videocassettes have contributed significantly to a reduction in mine accidents.

Jan 1, 1985

By Spencer P. Howell, J. F. Xrawshaw

"A recent premature explosion in a quarry that resulted in the death of nine men and the injury of several others, was directly traceable to a spark from a steam-shovel working under the face directly in front of the hole being loaded. This accident and similar accidents on record in the Bureau of Mines indicates the necessity for pointing out the dangers in quarries of explosives being ignited by sparks emitted from steam shovels and locomotives, and making recommendations for greater safety.Many premature explosions of which the following are examples, have resulted from sparks, both from steam shovels and passing locomotives. (A) The premature explosion occurred during August, 1920 at a limestone quarry, in a 100-foot drill hole, loaded with 1000 pounds of high-grade nitroglycerin and gelatin dynamites. This hole had been loaded with 500 pounds of 75 per cent strength gelatin dynamite, 300 pounds of 60 per cent straight nitroglycerin dynamite, and 200 pounds of 50 per cent straight nitro¬glycerin dynamite; but no steaming had been placed in the hole. The powderman loading the hole saw the spark enter the hole and was able to run a short distance before the explosion took place, thus escaping serious injury. The explosion of this first hole was transmitted to nearby hole similarly charged. The fall of rocks from these two holes buried the steam shovel and some of the gang of men working around it.(B) In September, 1909, in the Canal Zone, a steam shovel uncovered a misfired charge of dynamite. While the dynamite was being picked up the steam shovel continued working nearby. A spark from the shovel set fire to some loose dynamite spilled on the ground from the troken cartridges. This fire was transmitted to a hole which was being loaded close by and caused a premature explosion. One man was injured."

Nov 1, 1920