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By Douglas Ketcham, Thomas Jetzer

While the neurological and vascular aspects of Hand-Arm Vibration Syndrome (HAVS) has been generally accepted as a medical condition, the medical criteria and the clinical findings used to establish the diagnosis has been more difficult to bring to consensus. The criteria was first quantified by the Taylor-Palmear scale.1 This criteria was subsequently modified in 1986 at the 1st Stockholm Workshop2,3 to included more acceptance for the neurological effects that characterized the predominate findings in some workers. The relationship between hand-arm vibration and Carpal Tunnel Syndrome was defined in NIOSH 97-1414. While the aforementioned documents have defined the clinical entities associated with hand-arm vibration exposure, agreement on the clinical findings and test to confirm the diagnosis has be been more difficult to bring to consensus. Clinicians assessing HAVS has relied on a number of varied neurological and vascular tests. The neurological testing has focused on assessing damage to the sensory capability of the fingers for the neurological component including tests to measuring ability to sense vibration, cold or other end point finger sensor functions. However, the vascular testing has been traditionally focused on the ability to either measure vascular function or to reproduce the vascular blanching that occurs in HAVS with cold water provocation. Recent assessment of this testing in the United Kingdom Coal Miner’s study has questioned the value of this testing especially in reviews by McGeoch.5 In an attempt to provide some type of definitive testing to substantiate vascular damage from hand-arm vibration exposure, angiography is an alternative or adjunct to cold water provocation testing. The standards that have been established to predict the level, type and incidence of HAVS have been based on clinical studies and reports that have essentially been all male populations. However, the recent entry of women into more vibration intensive jobs has brought about the exposure of some women to high levels of vibration previously only previously experienced by men. However, there have been only few studies that look at HAVS in women6. Although exposed the same vibration levels, it has not been clear that the latency and type of pathology of HAVS in women will be the same as for men. The purpose of this study is to look at recent case studies of men and women exposed to jobs with high levels of hand-arm vibration with extensive clinical testing for both the neurological and vascular components of HAVS as well as other associated upper extremity conditions such as Carpal Tunnel Syndrome.

Jan 6, 2006

By L. A. Haas

In this Bureau of Mines investigation, conditions were determined to form an iron sulfide adherent coating with a metallic golden luster on steel upon anaerobic heat treatment with sulfur. The sulfide formation rate was determined in the temperature range of 105° to 500° C with reaction times up to 68 hours. The optimum temperature and time to form an adhering decorative coating on mild steel was in the range of 105° C for about 70 hours to 285° C for 1 hour. The golden coating consisted of an inner layer of pyrrhotite and an outer layer of pyrite. At temperatures higher than about 300° C, the outer layer thickness decreased owing to the decomposition of pyrite to pyrrhotite.. Small quantities (<0.5 wt-pct) of petroleum oil accelerated the sulfide growth rate. The sulfide coating decreased the corrosion rate of steel in a neutral aqueous medium by a factor of two. The dissolution of pyrite in water was dependent on particle size and surface area with the flat pyrite coatings exhibiting the lowest dissolution rate.

Jan 1, 1974

By G. R. Hopkins

[Apparent progress in fuel economy at petroleum refineries, as measured by the average amount of .seat units required to refine a barrel of crude oil, received a set-back in 1935, when the average rose to 562,00 B. t. u., compared with 562,000 B.t.u. in 1937 (see fig. l). The primary factor in the rise in average heat requirement&apos;s per barrel of crude oil refined in 1938 wan the decline in total runs to Invariably the average requirement increases when crude ins to stills decline, and vice versa. In other words, annual gains in fuel efficiency at refineries arc masked by the degree to which the capacity is utilized. Additional crude runs give lower average e heat requirements in two ways - first, because they are mane with the c expenditure of comparatively small amounts of auxiliary heat, and, second, because the additional runs generally represent simple topping operations. In 1938 crude runs, to stills declined 1.6 percent (from 1,183,440,000 barrels in 1937 to 1,165,015,000 barrels in 1938), but the total heat consumption declined only 0.4 percent, or from 663,866 billion B. t. u. in 1777 to 660, 56 billion in 1938 .]

Jan 1, 1939

By Raymond B. Ladoo

Garnets are usually found well crystallized in the cubic system , the principal forms being rhombic dodecahedrons , tetragonal trisoctahedrons or combinations of the two , and hexoctahedrons . They also occur as rounded disseminated glassy grains and in compact massive , laminated or gramlar aggregates . They vary greatly in color , but the most common garnets , almandite and andradite , are most often found of a dark red or reddish brown color .

Apr 1, 1922

By R. V. Higgins

This report presents the results of a study of gas injection in the Upper and Lower Terminal zones in fault block VB and in the Upper Terminal zone in fault block VI, Wilmington field, California. This report is based on data obtained to January 1956. Earlier studies of gas injection in other California fields have been reported .3/ The Upper and Lower Terminal zones, fault block VB, have been producing oil since 1945 and the Upper Terminal zone, fault block VI, since 1948. Before starting the gas-injection project, the expansion of dissolved gas was the principal mechanism moving the oil to the wells. Gravity drainage and an edgewater drive also have contributed to the movement of the oil to the wells. When the gas injection was begun, the reservoir pressure and the oil production had declined appreciably. Gas injection was started in the Upper and Lower Terminal zones, fault block VB, in May 1953 and in the Upper Terminal zone, fault block VI, in October 1953.

Jan 1, 1957

By Gerald A. Muson, Fremont F. Clarke

"INTRODUCTION The use of scrap mica as an industrial raw material has grown rapidly during the past two decades. Demands by various industries for ground mica for use in the roofing, paint, rubber, plastics, and wallpaper trades as well as for less extensive uses in insulation, oil-well drilling, welding, pipeline enamel, decorative material, and for other purposes exceed present (1947) supplies.A small proportion of the raw material used comes from the Black Hills of South Dakota, where casual recovery has been practiced in the exploitation of pegnatite deposits for more valuable minerals. The annual production of scrap mica in the Black Hills for the years 1939 to 1946 is shown in figure 19. 4/Although small, this production of scrap mica materially augments the incomes of numerous operators.Volume production of mica would offer attractive opportunities for obtaining steady and more economical supplies of the rare minerals as byproducts. Appreciable supplies of beryl, lithia minerals, sheet mica, tantalite-columbite, and cassiterite could accrue. Furthermore, a stable scrap-mica production would complement the production of quality feldspar, for which the Black Hills pegmatites are noted, and would help balance the economy of pegmatite mineral production.Mechanical methods of separation are requisite to production of enough scrap mica to be generally profitable. Various phases of the characteristics end treatment of mica have been investigated by the Bureau of Mines. A bibliography of these reports is appended.In 1945 the Bureau of Mines conducted pilot-plant tests to recover scrap mica by selective screening of crushed pegmatite. More recently the problem has boon studied in the Pegmatite Research Laboratory to aid in developing technological methods by which scrap mica may be separated from crushed pegmatite."

Feb 1, 1949

By Gerald W. Elger

This report describes development of the fusion-leach crystallization precipitation process for producing a hafnium content feed material for hafnium-zirconium separation plants. Mixtures of zircon, potassium silicofluoride, and potassium carbonate (or potassium chloride) were fused to prepare soluble potassium zirconium hexafluoride-potassium hafnium hexafluoride salts. High extraction of these salts was obtained by countercurrent leaching the fused material in dilute hydrofluoric acid. About one-half of the hafnium was recovered in hafnium-enriched mother liquor by cooling clarified lead: liquor to crystallize most of the zirconium salt. Additional hafnium was recovered from the primary crystals in a multiple dissolution-recrystallization step. Hafnium-enriched oxides having a hafnium-zirconium ratio of more than three times that of zircon were precipitated from the combined mother liquors. The hafnium and zirconium recoveries in the precipitate were 83 and 24 percent, respectively. About 71 percent of the zirconium and the remainder of the hafnium were recovered in potassium zirconium hexafluoride crystals of low-hafnium content.

Jan 1, 1966

This publication summarizes, for all interested parties, the research, development, and demonstration in-house projets programed by the Bureau of Mines for fiscal year 1980 (October 1, 1979 - September 30, 1980) under its Minerals Health and Safety Research program. The objective of these projects is to provide an ordered and sequenced series of advances toward the Bureau&apos;s overall goal of providing the system technology required to create a healthier and safer working environment for the Nation&apos;s mining and minerals processing workers.

Jan 1, 1980

By Will H. Coghill

The jig men of the Tri-State (Joplin-Miami) zinc district complain about the flakiness of their mill feed. They believe that the flakiness of the composite grains of gangue and mineral are to blame for losses of zinc; that is, that the flaky grains in the jig tailings have higher zinc tenor than the cubical grains. Although the evidence which follows contradicts this belief, no effort is made to give a final and conclusive answer. On the other hand, there is outlined a positive and mechanical method which the operator may use to pursue this and similar investigations. DISCUSSION OF SCREENING METHOD Hand-sorting is obviously not satisfactory for separating cubical grains from flaky grains because the personal influence can not be removed. Screens, however, may be used with success. A set of each of two types of screens is required; namely, the square-hole type and the rectangular (rectang, oblong) type. The square-hole screens must be of the double Tyler scale; that is, the order of the sieves should be after the fourth root of two instead of the customary square root of two; close sizing is important. The size of the rectang screens may be selected by trials so that a part of the material already closely sized on the square-hole screens, will pass the oblong holes. Obviously, the cubical grains will remain on the rectang and the flaky grains will pass through. Hence the mode of operation is to screen first on square-hole screens and then split the products on the oblong-hole screens.

Jan 1, 1928

By George A. Morgan

The production and processing of crude petroleum and natural gas are the dominant economic sectors of the Middle East. The IS countries that constitute the region accounted for 26% of world crude petroleum output, 17% of world natural gas plant liquid production, and almost S% of world dry natural gas production. About 66% of total world crude petroleum reserves and 31 % of total world natural gas reserves are in the Middle East. Transportation and port facilities in the region are geared to expediting efficient and rapid shipment of these materials. U.S.-dollar-denominated export sales of these fuels, estimated at $120 billion in 1989, provide funding for further diversification of the mineral industry. This is usually through development of downstream facilities for producing energy intensive metals such as aluminum and byproducts of the fuels such as petro-chemicals and fertilizers. Earnings from the industry are also channeled by sever-al Governments in the region to mineral industry projects in Africa and elsewhere. A fairly wide range of nonfuel minerals is produced in the region. However, the variety of minerals produced, output levels, and the size of the overall nonfuel mineral economy is dominated by Iran and Turkey. Turkey, with a diverse mineral production and strategically situated between Europe and the Middle East, ranked among the top three world producers of boron, chromite, pumice, and strontium. It was also a significant world producer of magnesium com-pounds, mercury, and sodium sulfate. Iran had generally lower output owing to 9 years of neglect to the mining sector between 1979 and 1988. It was a significant producer of gypsum and fifth in world production of strontium. Despite a very small domestic mineral industry, Israel was second in world production of bro-mine and a significant producer of phosphate rock and potash. Jordan ranked fifth in world production of phosphate rock. Iraq ranked about eighth in world production of sulfur, a commodity of major importance in the metallurgical, petrochemical, and fertilizer industries.

Jan 1, 1992

By L. B. Pankratz

Thermodynamic data on the elements and oxides were reviewed, evaluated, and compiled at the Bureau of Mines Albany Research Center. Values for Cp°, S°, H° - H°298, - (G° - H°298)/T, ?HP, ?Gf°, and log K are given in tabular form. Cp°, H° - H°298, ?Hf°, and ?Gf° are also expressed algebraically. Examples of calculations using these data are given.

Jan 1, 1982

By John H. Johnson

White Pine Mine section designated for exhaust emissions studies. The MTU Mine Air Monitoring Laboratory was used to gather temperature and C02 concentration data at 10 locations. The data substantiate the presence of strong buoyant forces of the hot exhaust gases which result in stratification in dead end headings. Diesel mine-vehicle tailpipe emissions were monitored in the laboratory by a portable tailpipe emissions measurement apparatus (EMA) assembled for in-mine use. The results were compared with simultaneous measurements by standard laboratory exhaust monitoring instruments. These results indicate that accurate field source quality control measurements can be obtained for CO2, CO and NO but NO2 results were low for all engine conditions. Diesel pollutant concentration data from the Orchard Valley Mine were analyzed and compared with data collected earlier in the White Pine and Brushy Creek mines. Lognormal frequency distributions and CO2-based concentration ratios and correlations were calculated. In the three mines compared, pollutant concentrations were distributed similarly, and concentrations appear to be controlled to present standards.

Jan 1, 1979

By H. C. Miller

"Introduction**The progress of the ""Safety First"" movement in the oil fields of California during the past few years has been remarkably rapid. It has been generally concede by those who have learned to value the life and limbs of their employees, that safety is essential to efficiency and no company that has a high accident rate can be considered an efficient organization. Accidents have a destructive effect on the morale of any body of workers and cause disorganization and delays.The increasing danger to life and limb involved in the drilling for and the production of oil and gas, has become so great that it is clearly evident that everything possible must be done to keep it within the narrowest possible limits.There is a tendency toward carelessness, especially by men who are employed in hazardous occupations. This is brought about by the familiarity of the risk under which they are working and in no industry is this more forcibly exemplified than in the oil fields. Men have performed the same or similar duties for many years and have worked around similar hazards and unprotected machinery until many have can entire disregard for the dangers surrounding then. Very often familiarity with a hazard occasions a contempt for that hazard which only too often results disastrously."

Dec 1, 1923

Mining activity during 1977 was limited to the production of limestone, marl, and sand and gravel, all of which were used domestically. Public works projects consumed the major portion of the construction material produced. The consortium of oil companies operating as Esso Ventures Inc., drilled one exploratory well off the coast of southern Belize. For drilling the well, Exxon Corp. received a 57% working interest in the consortium&apos;s concession located 40 kilometers east of Puta Gorda. No other offshore drilling was attempted in 1977. Esso also drilled a well on the Anschutz Overseas Inc. concession in the Toledo District of south- eastern Belize. The attempt wee abandoned, but seismic activities continued.

Jan 1, 1981

By C. T. Baroch

As part of a general program for investigating all phases of titanium production, argon was substituted for helium in the reduction step at the Bureau of Mines pilot plant, which employed a modification of the Kroll, or magnesium-reduction, process. Argon was substituted for helium in 108 of the 140 batches of sponge made during 1 month&apos;s reduction operations for July 1954. Argon was substituted for helium satisfactorily, with only slight modifications in technique. Metal quality, feed rate of TiC14, magnesium efficiency, and average production per batch were closely comparable with either gas. Argon runs were slightly more troublesome because of the formation of condensable chloride complexes, which tended to plug feed and vent lines and to entrap deposits of lower titanium chlorides on the reactor-pot lids. These lower chlorides were objection-able because they were pyrophoric and created obnoxious fumes when pots were opened. When feed and vent lines became plugged care was required in poking or unplugging these lines to prevent air from entering the reactor. These problems were relatively minor, and continued development of reactors and techniques for the use of argon should further minimize objectionable side reactions obtained when argon is used.

Jan 1, 1956

By Lorenz E. Sieffert, Lawrence B. Berger, H. H. Sehrenk, Ralph W. Stewar, James A. Gale

"INTRODUCTION The purpose of the investigation discussed in this article was to evaluate the toxic hazard from gases produced when thermosetting plastic materials used for electrical insulating purposes are burned or thermally decomposed in enclosed spaces. For brevity the term ""toxicity"" is used throughout the article to refer to the nature of gases produced under these conditions. A need for immediate study of the problem was created as a re¬sult of the battle damage reports received from various United States Fleet units. These indicated that the fumes emitted when these materials were burned or thermally decomposed had, in several instances, resulted in toxic atmospheres. In attempting to develop a suitable test method for evaluating toxicity, it was recognized that no single test procedure could be expected to duplicate the variety of conditions that might exist in an actual fire aboard ship. In view of the immediate need, however, it was felt that considerable information could be obtained, at least to classify comparatively the several types of materials as to the toxic effect caused by burning or thermal decomposition, through the development of a sound empirical method which could be applied to all of the materials. On this basis, it was decided to modify the Navy flame resistance test for thermosetting plastics to render it applicable to the determination of the toxic, gases evolved when this test was employed. A wide variety of materials was tested, both molded and laminated, to cover the types commonly used by the Navy in electrical applications. Toxicity determinations were conducted at the Bureau of Mines Central Experiment Station, Pittsburgh, Pa. Parallel tests, to determine the flame resistance of the materials, were conducted at the Material Laboratory, U. S. Navy Yard, New York, N. Y."

Oct 1, 1947

By Dayton C. Bolin

This paper is one of a series being prepared by the United States Bureau of Mines describing quarrying methods and costs at stone quarries 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 production costs. It is recognized that publication of total production 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 scrope of the cost tabulations shall ensue. ACKNOWLEDGMENT The author wishes to acknowledge the assistance of J. R. Thoenen, mining engineer, United States Bureau of Mines, in the preparation of this paper. Acknowledgment is also made to E. R. Lederer, vice president in charge of the company&apos;s operations, through whose kindness the preparation of this paper was made possible. E. T. Eubank, superintendent of the quarry, and J. A. Hodges, quarry foremen, gave much of their time to this work. The cost data were compiled by the company&apos;s chief clerk, J. von Carlowitz.

Jan 1, 1931

By J. C. Fowler

[This i.untra t hds bmii III c&apos;IIILt fur till- past 1&apos;:?:u yrlr;, Till-- wurir pnrfor rw:it &apos;. ,JS hlui.rn dawn Ilttf lit Iu i eel i ih?IS( S. 1 hesrt aIII, Phase I Candor tlri I a lest It) donurnSlrale SeiSrrlir nurihudS to hu USi!d lot ttlr? rti?tei thin and Iu" ainnl ul trapped rrlinc:rs hitting (-)it the roof with a harnrner, Phase I&apos; Design and cunStrur.t a permanent Seismic monitor System to rrlunrtur roof (ails arm r:xploslun&apos;, III ,r &apos;Vol king mine. Phase III - Ire dII an an i i irr for sVstl rtl Ii i`&apos;Smltur air quality in till, niitii iiH II ? ir,iti tin; niln !III ;I I ,, i; Phase I V - Conduct 11(21 d tests of the seismic IT IUnit UT ieq system fur a period nl two 11IUIIIIIS. Phase, V - Condirct three test periods of the seismic system over a period of six mimilis. Detailed reports covering the wurk. done in Phases I, 11, and IV have been i : . r tr I - i t report will, therefore, cuni.entrate on the work perfurmed in Phases III anti V.]

Jan 1, 1975

By John J. Baz-Dresch, Kenneth L. Bickel, Winthrop F. Watts

Catalyzed diesel particulate filters (CDPF&apos;s) reduce the concentration of diesel particulate matter (DPM) and may reduce the emissions of carbon monoxide (CO) and hydrocarbons (HC) in diesel exhaust. Asamera Minerals&apos; Cannon Mine first installed CDPF&apos;s in 1987, and currently has 12 diesel- powered vehicles equipped with CDPF&apos;s. The Cannon Mine and the U.S. Bureau of Mines collaborated to evaluate the durability and performance of a CDPF. One of the CDPF&apos;s used at the mine was periodically evaluated in the USBM&apos;s diesel emissions laboratory after 839, 1,584, and 2,881 h of in-mine service. The objectives of this report are to present results from the USBM&apos;s evaluation of this CDPF, to describe the Cannon Mine&apos;s experience and cost analysis of using CDPF&apos;s, and to make recommendations for the future use of CDPF&apos;s. CDPF&apos;s improve air quality at the Cannon Mine, but they frequently become plugged and are subject to excessive mechanical shocks and stress, shortening their useful life. Mine records indicate that CDPF&apos;s account for 0.8 to 4.9 pct of the vehicles&apos; operating cost at the mine. CDPF life to date has ranged from 1,671 h to more than 5,992 h. Laboratory tests of the CDPF determined that DPM removal efficiency decreased and regeneration temperature increased over time.

Jan 1, 1994

By J. C. Gerdeen

SAP-S information on the following element types are included in this appendix: Type 1. Three-Dimensional Truss and Bolt Element Type 4. Two-Dimensional Finite Elements Type 8. Variable-Number-Nodes Thick Shell and Three-Dimensional Elements Type 9. Two-Dimensional Joint Element (to be used with Type 4 elements) Type 10. Three-Dimensional Joint Element (to be used with Type 8 elements) Additional SAP4 elements, Types 2, 3, 5, 6, 7 and 12, are also contained in SAP-S and information on these elements is readily available in any SAP4 user&apos;s manual. These elements are as follows: Type 2. Three-Dimensional Beam Elements Type 3. Plane- Stress Membrane I-r .n Elements Type 5. Three-Dimensional Solid Elements (8 Node: Brick) Type 6. Plate and Shell Elements (Quadrilateral) Type 7. Boundary Elements Type 12. Three-Dimensional Straight or Curved Pipe Elements

Jan 1, 1976