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By Ludwig Schmidt

The policy of buying crude oil on a gravity basis , recently instituted by the major crude oil purchasing agencies in the Mid- Continent field , has caused a new and vital interest to be taken in the work of the U. S. Bureau of Mines for preventing evaporation of crude . From the early years of the industry oil men have recognized that the gravity of crude oil is usually an index of the gasoline content , but it has not been so generally known that the gravity of the crude oil decreases if evaporation is permitted . In 1919 the Bureau of Mines began a survey to determine the evaporation losses of crude petroleum in its various stages of handling from the well to the refinery , The results of this study are presented in Bulletin 200 ( Wiggins , J.H. , Evaporation losses of petroleum in the Mid- Continent Field , Bulletin 200 , U. s . Bureau of Mines , 1922. ) and Bulletin 225 ( Wiggins , J.H. , Methods of decreasing evaporation losses of petroleum , Bulletin 225 , U. S. Bureau of Mines , ( In press ) The findings of this survey were so startling that soon after the preliminary report had been published , several tank companies began manufacturing vapor- tight tanks for the purpose of reducing these important losses . Since that time the development of this type of apparatus has been so rapid that today , every oil trade journal carries numerous advertisements of vapor- tight tanks and equipment as well as technical articles dealing with various problems in connection with the elimination of evaporation losses , whereas three or four years ago the subject was scarcely even thought of. The present report has been prepared in response to numerous requests for information on the apparatus actually being used to prevent evaporation losses . At this time oil operators are also extremely interested in holding the lighter fractions in the crude oil in order to prevent a lowering in gravity . The practice of removing the vapors from crude- oil tanks by means of a slight vacuum and extracting the gasoline from them is not discussed here .

Feb 1, 1923

By Fred N. Kissell

A parachute-type stopping intended for changing the course of mine ventilation air during mine emergencies has been designed and tested. Some production uses are also visualized for metal mines. Preliminary tests in the laboratory and underground indicate that the parachute stopping is a workable concept, but further developmental research is required.

Jan 1, 1975

Develop and evaluate a mechanical position and heading system (MPHS) that provides information about underground mining machine position and heading to aid in the remote positioning of mining machines during face maneuvers. Background While great improvements have been made in mineworker safety, progressive technology continues to create a safer, better working environment for miners by keeping them away from the dangerous face area. In maintaining such high standards of safety, the Bureau is investigating remote, computer-assisted operation of mining systems for underground, highwall, and surface mining applications. A key component of computer-assisted operation is a guidance system. Since there are no guidance systems on any commercial continuous mining machines, the Bureau itself developed and tested the mechanical position and heading system (MPHS). The MPHS is based on linear position transducers (LPT's), and operates on principles of triangulation to provide machine position (xy coordinate), and orientation in the xy plane (yaw or heading). These data are needed in order to keep the continuous mining machine in proper alignment before and during the cutting cycle. The MPHS theory development is in three parts: characterize the sensors used and their configuration; select and define the navigation reference frames; and derive a closed-form solution for determining the position and beading from sensor information. Application of the MPHS theory required the development of hardware, software, and system interfaces.

Jan 1, 1992

By L. C. IlsLey, H. B. Freeman

In connection with the approval of coal-cutting machines for service in gaseous mines , the engineers of the Bureau of Mines have been somewhat concerned as to the type of trailing cables that could safely be used on permissible outfits . While no final action has been taken on this question ( tentative approvals having been granted pending investigations ) , the Bureau has been endeavoring to collect data and information on this question which would permit a fair , yet safe , ruling to be made . For this purpose cooperative arrangements were made with three coal companies to visit certain of their mines , making inspections inside the mines to observe the cables and cutting machines in operation . In all , twenty mines were visited . A questionnaire covering the operations of trailing cables was filled out at each of these mines . In a few instances no personal inspection was made , the information being supplied by mine officials after conferences with the Bureau's engineer . At other mines the information given by mine officials was supplemented by personal observation inside the mines , usually at a time when the cutting machines were in operation .

Jul 1, 1923

By G. W. Jones

In the course of experiments on the stabilization of acetylene gas by addition of other gases, notably hydrocarbons such as methane, propane, and butane, it was observed that large quantities of carbon black are produced during the explosion of acetylene or mixtures of acetylene with the, above hydrocarbons, the added hydrocarbon being essentially decomposed into hydrogen and carbon. It is known that in the complete absence of air acetylene explodes upon application of an intense ignition source at pressure above 5.9 p.s.i. gage. The same is true of mixtures of hydrocarbons and acetylene. However, the pressures necessary for explosion are considerably higher in the case of these mixtures and depend on the amount of added hydrocarbon. The present report contains data on gaseous products and the physical characteristics of the carbon black formed by explosion at elevated pressures of various mixtures of acetylene and hydrocarbons as well as other gases, such as hydrogen, helium, nitrogen, and carbon dioxide.

Jan 1, 1950

By Jianmin Qin, Raja V. Ramani, Wilson Miola

"The number of underground work entities operating under reduced dust standards in U.S. coal mines has been increasing since the start of the decade of the 80s and is currently approaching 10,000. The concern for controlling the quartz levels in airborne respirable dust in coal mine has manifested itself in several improvements in equipment selection and operation, face ventilation practices, and dust control procedures. At the same time, fundamental studies have been initiated on determining the source-sink relationships of the airborne quartz dust. The P-7 method is the prescribed method for the determination of quartz in the respirable airborne dust samples from coal mines. Questions have been raised on the reliability of the P-7 infrared spectrometry method for quartz analysis in powders. No specific method has been defined for quartz determination in bulk samples from the mine.In a recent study on the relationship between quartz in the airborne dust and that in the materials being mined, both infrared (IR) and x-ray diffraction (XRD) methods were used on a suite of samples from several coal mines. These samples encompassed airborne respirable dust samples, airborne total dust samples, the oversize fraction from the respirable samplers, ROM samples, channel samples, and chip samples from the face, roof, and floor materials. In this paper, the sample preparation and analysis procedures for the samples are discussed. The data, analysis results, and comparisons of the P-7 and XRD results are presented. The quartz percent determined for the same sample by the two methods are different. In 85% of the samples analyzed, the quartz percents determined by the XRD method are higher than those obtained by the P-7 method. However, there is a strong linear relationship between the results from the two methods. Further, the XRD method indicates an average of 20 percent more quartz than that from the P-7 method. The reasons for the differences in the results and the need for additional studies are explored.Since the enactment of the Federal Coal Mine Health and Safety Act of 1969 and the Federal Occupational Safety and Health Act of 1970, the prevalence of free silica as an occupational hazard in dusty work environments has been a matter of increasing concern. In underground coal mining, sometimes, roof, floor, clay veins and other non-coaly material must also be mined along with the coal. Mining these materials may increase the amount of quartz in the airborne dust (Pimentel and Adam, 1985; Taylor et al., 1984; Colinet et al., 1985). The problem of high quartz levels in the respirable airborne dust is widespread in continuous miner sections. In addition to the need for controlling the silica amount in mine atmosphere, a need for a sensitive, easily performed method for the determination of free silica in airborne dust samples was also recognized."

Mar 1, 1992

By William J. Campbell

These investigations were undertaken as part of a program to determine the optimum X-ray spectral lines to use for analyzing the wide variety of samples received by the X-ray Laboratory. Theoretical calculations and experimental data derived from these investigations show that longer wavelength spectral lines, > 2A, are very useful for many analytical problems. Because of the low fluorescence yield of the elements of atomic numbers 13-22 and the small depth of penetration of their X-ray spectral lines, these elements were originally considered to be insensitive; however, these studies show that the wide dispersion of their spectral lines, coupled with their weak beta lines, permits the use of wide collimation, thus increasing the line intensity. More importantly, the background due to scattered primary radiation is very low in the long-wavelength region.

Jan 1, 1959

By Frank C. Andreuzzi

The Division of Environmental Activities, U.S. Bureau of Mines, conducted a solid waste demonstration project on a burning coal refuse bank. The primary objective of this project was to develop and evaluate an efficient method of extinguishing burning coal refuse and moving it. A series of tests were performed using water monitors and related apparatus to quench the burning material and, at the same time, using earth-moving equipment to transport, spread, and compact the extinguished material. The method found to be most effective consisted of water-quenching the surface material to a workable depth, ripping, and removing the quenched material with a bulldozer and tractor-scraper. The total cost was estimated to be $0.44 per cubic yard.

Jan 1, 1970

By P. C. Good

High-purity chromium was prepared in massive form by the electrolysis of chromium trioxide solution at high temperatures. The metal thus obtained, containing 50 to 150 p.p.m. of oxygen, 20 p.p.m. of nitrogen, and traces of metallic impurities, could be hot-worked to rod and sheet and drawn to wire ductile at room temperatures. Optimum concentrations and operating conditions were established for the deposition of chromium from chromic acid baths containing sulfate, fluoride, and silicofluoride ions. Current efficiencies of 13 percent were attained with baths containing sulfate ion, and efficiencies of 40 to 44 percent with baths containing fluoride and silicofluoride ions. Cation exchange resins were used for removing metallic impurities from chromic acid solutions containing sulfate ion; solutions containing fluoride and silicofluoride ions were purified by recrystallization.

Jan 1, 1960

By J. M. Stuve

Low temperature and high-temperature calorimetric measurements were made by the Federal Bureau of Mines on high-purity samples of Re02(s) and Re03(s) to determine heat capacities and enthalpies. The temperature range of heat capacity measurements was 5 to 310 K for Re02 and 8 to 309 K for Re03. High-temperature enthalpy measurements alone were determined for pure Re207(s,1). The derived standard entropies are S°298 = 11.43±0.01 cal/deg mole for Re02(s) and S298 = 16.55±0.02 cal/deg mole for Re03(s). High-temperature enthalpy equations expressed in calories per mole are as follows: Re02 (s) , H-H298.15 = 16.002T + 1.600 X 10-3T2 + 3.522 X 105T-1 - 6,095 (298 to 1,400 K); Re03 (s) , H-H298.15 = 20.293T + 3.238 X 10-3T2 + 3.950 X 105 T-1 - 7,664 (298 to 1,000 K); Re207 (s) , H-H298.15 = 38.437T + 10.309 X 10-3T2 + 4.315 X 105 T-1 - 13,824 (298 to 413 K); Re207 (s) , H-H298.15 = 30.181 + 17.713 X 10-3T2 - 10,612 (413 to 600 K) ; Re207 (1) , H-H298.19 = 66.101T - 10,092 (600 to 700 K). Gibbs energy of formation (?Gf°) data and related functions over the temperature ranges investigated are tabulated for the three oxides.

Jan 1, 1976

By Robert E. Barieau

This report gives the principles of the method used by the Helium Research Center of the Bureau of Mines when solving nonlinear-regression problems and contains the mathematical equations necessary to accomplish the following objectives: the evaluation of the parameters in such a way that the sum of the weighted squares of the residuals of an experimental observable is a true minimum, regardless of the functional relationship between the variables and these parameters; and the evaluation of all variances and covariances of the parameters by means of the usual approximation of the law for the propagation of errors.

Jan 1, 1967

By A. F. Cohen

When location guidelines are followed in choosing sites for fixed point velocity transducers for use in underground coal mine monitoring, mine air turbulence intensities <11% are generally expected at those sites. The objective of this Bureau of Mines investigation to determine the effect of turbulence intensities <11% on vortex shedding sensors and transducers. Measurements were made at velocity levels of interest for underground coal mine monitoring use (?200, ?500, ?1,000, ?1,500 ft/min). The effect of grid-produced turbulence intensities (2% to ?14%) on the output of vortex-shedding air-velocity transducers was less than ±10%.

Jan 1, 1985

By V. F. Parry

"INTRODUCTION During the war period the Bureau of Mines expanded its investigations on western coals principally in connection with Investigations of raw material resources for western steel production. Owing to the expansion of the steel industry, there was some concern regarding the availability of suitable coking coals; end because of the potential steel shortage, the production of sponge iron, using the lower-rank fuels, was considered. Work was conducted by the Bureau of Mines on exploration projects and on testing of coals both at the Central Experiment. Station at Pittsburgh, Pa., and at the Bureau of Mines Station at Golden, Cole.The results of these investigations are being published by the Bureau in several reports of investigations and technical papers. In making this resume of coal investigations, the work done by the Bureau of Mines at Pittsburgh in the Mining and Coal Carbonization Sections will be discussed and the investigations at Golden described in greater detail.INVESTIGATIONS OF WESTERN COALSThe Mining and Coal Carbonization Sections of the Coal Division, Bureau of Mines, under the supervision of A. L. Teeny es and J. D. Davis, respec¬tively, conducted many field investigations to locate and evaluate new sources of coking coals. Drilling explorations were made in Colorado, Wyoming, Utah, New Mexico, and Washington and revealed two important new reserves of coking coal. The first one studied was the Willow Creek bed at Kemmerer, Wyo., which was reported in 1945.3/ A recoverable reserve estimated at 11,200,000 tons was blocked out, and samples of coal were extracted for coking tests. The coking properties of the coal were not quite equal to those of Sunnyside coal, but it was indicated that a 50-percent blend of the Willow Creek with Lower Sunnyside will produce a satisfactory metallurgical coke based on Columbia steel standards."

Jan 1, 1948

By G. W. Weems

The Bureau of Mines combined preconcentrating techniques and mass spectrometry to develop a parts-per-billion general analysis of impurities in helium. The impurities are preconcentrated using a Bureau trace-impurity analyzer; 35-mm Hg pressure of helium is left in the concentration trap to sweep the impurities into the mass spectrometry and provide a 10-mm Hg sample pressure.

Jan 1, 1966

By Oliver Bowles

Wire saws have been used for many years in European travertine, marble, and slate quarries. This method of sawing found very limited use in America until 1927 when it was accepted as standard equipment in elate quarries in Pennsylvania where it has been remarkably successful. Details of its operation in slate have been published in a recent bureau report.3 The very limited extent to which the wire saw has been employed in limestone and marble quarries in the United States and the seeming lack of interest even in experimental work to determine its advantages are difficult to explain in vied of its wide use in cutting similar rocks in Europe and its unquestionable advantages in sewing slate in America. In order to encourage improvement in quarry practice the United States Bureau of Mines has endeavored to obtain information as to the extent to which wire saws are used in Europe together with data on the rate and cost of sawing. The information at hand is by no means complete either in territory covered or in details of operation; it nevertheless brings out certain significant features that may be of interest and advantage to quarrymen in the United States.

Jan 1, 1931

Construction workers may be exposed to hazardous dust containing crystalline silica during site preparation when drilling systems are used. The National Institute for Occupational Safety and Health (NIOSH) found that drill dust could be decreased by using wet or dry dust reduction engineering controls, enclosed cabs, and implementing a dust control program.

Jan 1, 2009

By C. A. Allen

"The problem of signaling to the hoisting engineer from a moving cage in the shaft has been considered by many mine operators for a number of years. There are several methods in use in different mining districts, and so far as the writer is aware they have been further developed in Utah than in any other state. The latest installations are of interest because they use a very low-voltage circuit for the shaft wires and also because the wiring can be so arranged that the hoist can be stopped from the cage, if so desired.The first installation in Utah was in the shaft of the Centennial-Eureka mine under the management of C. E. Allen. It was placed in operation in the summer of 1899, end has been in continuous and satisfactory operation for 21 years. The arrangement consists or two bare wires down the shaft carrying a current at 60 volts potential, with a device on the cage for making connection between the two wires. This device is simply a short piece of wire which is thoroughly insulated from the cage and is operated by a short lever. Whenever the cage rider wishes to signal the engineer he pulls down the lever, forcing the short wire out against the two bare wires, thus making a circuit which rings the bell in the hoist-room. A similar device was planned in the Grand Central shaft at Mammoth, Utah, but was later abandoned. The cause of failure was reported to be that the shaft was very wet."

Jun 1, 1920

By R. V. Ramani

"In a 1985 seminar, we were told that over-optimism abounds in Artificial Intelligence (AI), that AI is neither a science nor a technology yet, and that we will be both exhilarated and disappointed with AI. In fact, even today, there is no single accepted definition of AI; however, certain features have been identified by AI researchers as essential to consider an entity (e.g. machine or program) to be intelligent. According .to Shank (1987), these features include communication (to be able to communicate with), internal knowledge (knowledge about itself), world knowledge (awareness and knowledge about the world outside), intentionality (knowing what one wants and a plan to seek it, ie. goal seeking behavior), and creativity (being adaptable to changing conditions). None of these figures would individually define intelligence; however, each would be a part of intelligence in its own way.The prospects for the development of entities with AI have never been as good as they are now. The combination of advancements in computer hardware and .software along with new insights into the ways in· which we store knowledge and use it for problem solving has enhanced the potential for the creation ~f intelligent entities. After some unbounded optimism of a major breakthrough in the fifties and frustrating disappointments in the two following decades, it appears now that AI has emerged from research labs to industrial practice. This is confirmed by the growing number of repeat applications of AI in business and industry to the extent that AI can now be considered a technology.AI applications are categorized into several distinct areas such as Natural Language Processing, Speech Recognition and Synthesis, Expert Systems, Robotics, Machine Vision, etc. Of these practical realizations, Expert Systems (ES) has the greatest potential for meeting the decision-making needs of the manager in the ever-growing complex scoio-technical systems. Prof. Feigenbaum, an expert and leader on expert systems, has defined Expert System as"" ... an intelligent computer program that uses knowledge and inference procedures to solve problems that are difficult enough to require significant human expertise for their solution. Knowledge necessary to perform at such a level, plus the inference procedures used, can be thought of as a model of the expertise of the best practitioners of the field."""

Jan 1, 1989

By W. P. Yant, G. W. Jones

During the testing of porcelain insulators with a " 60 - cycle flash - over apparatus " , gases are liberated having an odor greatly resembling that of ozone . Since the two main constituents of normal air are nitrogen and oxygen , and high voltages (approximately 90,000 volts ) are used during the tests , the conditions are favorable for the production of ozone or oxides of nitrogen , and perhaps both simultaneously . The presence of these gases is only noticeable during the testing period . They soon disappear after the test is over . No fatalities have ever resulted from these gases at the plant visited nor are there any records of any of the men who worked on the tests being confined to their homes from this cause . New employees sometimes complain of a depressed feeling and shortness of breath , which is most noticeable after leaving work and getting into fresh air , but they som become accustomed to it and no ill effects are noticed . In view of previous work*** which the Bureau of Mines has done on oxides of nitrogen in connection with mine gases and problems in gas analysis , tests were made at the plant of the Westinghouse High Voltage Insulator Company at Derry , Pa . to determine the kind and amount of gases liberated .

Jun 1, 1923

By Lloyd Williams

1. The investigation shows that the Wilder (locally known as the Bon Air No. 2) is the only known bed of commercial importance in Putnam County, although at least 5 coal horizons are known. All of the coal production now reported comes from this bed, which is found In a basin with no known coal outcrops. Further drilling in the east end of the basin should disclose the location of the eastern end of the axial trough and the lateral extent of the basin in Putnam County and adjoining areas in Cumberland County. Continuity of this deposit with that in the area in Putnam County north of Monterey is not conclusively established but may exist. 2 Known (measured plus indicated) reserves of coal, based on a minimum bed thickness of 14 inches and on 1,800 tons per acre-foot in place, are estimated at 29 million tons, as of January 1, 1953. Of this total, 28 million tons are in beds 28 inches and more thick. All born coal reserves in Putnam County me under less than 400 feet of overburden.

Jan 1, 1954