Search Documents

By L. M. Demers, D. C. Kuhn, N. El-Ayouby, C. F. Stanley

"Oxygenated metabolites of arachidonic acid (MJ are produced by the alveolar macrophage (AM) and have been shown to mediate inflammatory reactions. We therefore assessed the production of eicosanoids by AM harvested from the lungs of rats ex· posed to a bituminous coal dust for 2 wk in an inhalation chamber in order to determine if AA metabolism was altered in a manner that may promote an inflammatory response in the lung. Exposure to coal dust resulted in a 66% increase in the number of AM harvested, an increase in thromboxane A2 (TxA;i) and leukotriene 84 (LTB,j) production to 222% and 181% of control values, respectively, and a decrease in prostaglandin E2 (PGE:i) production to '62% of control values. In AM harvested from rats allowed to breath clean air for 2 wk following coal dust exposure, PGE2 production returned to control levels but TxA2 and LTB4 production remained elevated. The TxA2 synthesis inhibitor UK 38,485 reduced TxA2 production in dust-exposed AM both immediately and 2 wk following exposure. Thus, exposure of rats to coal dust significantly alters the metabolism of AA in AM, with potentially important aspects of AA metabolism remaining altered even after a 2-wk recovery period. Based on the established role of eicosanoids in inflammatory and fibrotic processes, these results suggest that the alteration of AM eicosanoid production as a result of the inhalation of coal mine dust may be an important factor in the pathophysiology of coal workers' pneumoconiosis.The authors are grateful to Joan Greenwood and Barbara Scheetz for their excellent technical assistance and to Brenda Pavone for the preparation of the manuscript. This research was supported by the U.S. Department of The Interior's Mineral Institute Program administered through the Generic Mineral Technology Center for Respirable Dust under grant 1135142.Request for reprints should be sent to Douglas C. Kuhn, Ph.D., Department of Pathology, The M.S. Hershey Medical Center, Hershey, PA 17033.INTRODUCTIONPulmonary alveolar macrophages (AM) are activated by foreign particles and microorganisms that enter the small airways (Kass et al., 1966; Herscowitz, 1985). This defensive reaction involves phagocytosis, lysosomal enzyme release, and the generation of reactive oxygen species by the AM (Snella, 1986; Rich et al., 1987). A number of agents, including phorbol esters, zymosan, adenosine diphosphate, organic hydroperoxides, and calcium ionophore, have been shown to activate the AM in vitro (Badger, 1986; Marshall and Lands, 1986; Snella, 1986). The AM response to these activators appears to be mediated in part by the oxygenated metabolites of arachidonic acid (AA) (Bertram et al., 1988; Demers et al., 1987; Mcleish et al., 1987).The AM may metabolize AA through cyclooxygenase- and lipoxygenase- catalyzed pathways to produce a variety of eicosanoids including prostaglandin (PG) E2, thromboxane (Tx) A2, leukotriene (LT) B4, LTC4, LTD4, and several hydroxyeicosatetraenoic acid derivatives (HETEs) (Willis, 1970; Camp et al., 1983; Poubelle et al., 1986). The production of these eicosanoids may enhance the. defensive ability of the challenged lung since they stimulate chemotactic cell recruitment to the site of invasion, enhance extravasation of circulating immune cells, and promote local vasodilatation. However, continued stimulation of the AM population, with the consequent production of proinflammatory eicosanoids, may ultimately enhance the disease process by contributing to chronic bronchoconstriction, fibrosis, and the persistent release of toxic oxygen species."

Jan 1, 1990

By Harry R. Johnson

Domestic expenditures by the U.S. petroleum industry have exhibited distinctive shifts in emphasis over the past 20 years. From the end of World War II to 1955, expenditures for all phases of the industry expanded. Although over one-half of all expenditures were for production, the relative emphasis was changed after 1956-58 from production toward processing and marketing. The period 1967-69 marked the beginning of a return to emphasis on exploration and production. These trends in expenditure patterns are logical and rational when related to domestic and international economic conditions and to the widespread application of improved production technology. As the immense job of developing the oil resources of Alaska and other regions begins, the petroleum industry will continue to turn to external sources for working capital. Long-term debt will probably be the principal method of external financing through 1970, but a definite shift toward new common and preferred stocks will be made. Higher product prices may be sought by the petroleum industry, but the economics of crude-oil production, changes in the tax structure, and possible changes in the oil imports control program make the price structure of crude oil and crude-oil products unpredictable at the present time.

Jan 1, 1970

By R. R. Sayers

Mine operators and managers for a number of years have known that the maintenance of health among the workers has an appreciable financial value, In order to maintain the health, it has been found ne cessery to imow; 1. The health hazards existing in the industry as a whole and the specific hazard in the individual mine. 2. The physical condition of applicants for employment as well as that of the old employees. This can be determined only by systematic physical examination of all applicants and of regular employees at intervals of at least once a year thereafter. 3. All cases of sickness that occur among the workers. No operator or manager, or personnel, medical, or safety organization can control or prevent sickness without knowing where, when, and under what conditions the sickness actually occurs. In order to obtain information as to the hazards of industry, investigations have been and are being made of the effects of the condi- tions both in the field under usual working practices and in the laboratory. In the field several factors are generally present which affect the health. The effect of these factors may be determined by studying each of them separately in the laboratory. However, both the field and the laboratory studies are limited in value in that such studies usually have been made over a comparatively short period. While we have some information as to their immediate effect, we do not know to what extent extreme heat, humidity, the presence of dust or other health hazards are the cause of disability. Mortality statistics are probably the most easily available indices as to the hazards of industry. As an example, a study of such statistics among coal miners of Indiana shows a marked increase in the death rate in 1918.

Mar 1, 1923

By R. L. Benner

A compound stability diagram was constructed by the Bureau of Mines for the Zn-Fe-S-O system to show the phases that should be thermodynamically stable at various temperatures, oxygen pressures, and SO2 pressures. The diagram was demonstrated to have good qualitative value for predicting stable phases that may, in turn, be related to the recovery of zinc in the leaching phase of the electrolytic zinc process. The study showed that roasting temperature is the most Significant variable in preventing roaster formation of zinc ferrite, which is directly related to subsequent extraction of zinc in the leaching step.

Jan 1, 1966

By John P. Coughlin

The Bureau of fines has tested a portable microseismic processor recorder at the Galena Mine, Wallace, ID, both in an environmentally controlled enclosure and, with minimal protection, in a working area of the mine. In both trials the device demonstrated effective and reliable data acquisition capabilities.

Jan 1, 1985

By E. K. Kleespies

The rate of the heterogeneous reaction between titanium-oxygen solid solutions and titanium trichloride in molten sodium chloride was determined at high temperatures. In the alpha phase, the reaction rate decreases uniformly with the increasing concentration of oxygen. The gamma crystalline form of titanium (above 33 atomic percent oxygen) was much less reactive than the alpha phase, and the reaction rate approached zero at 50 atomic percent oxygen. The activation energy for the reaction of titanium-oxygen solution containing 22.8 percent oxygen was 11.7 kcal/mole of TiCl3 as compared with 8.3 kcal/mole of TiCl3 for pure titanium.

Jan 1, 1967

By F. S. Crawford

The average visitor to a large electric-shovel operation may wonder how electric power can be treated as carelessly as apparently it is in open-pit mining, and how the mining company can string it carelessly along the ground in great, black, hoselike cables, whereas the power company, which has learned to respect his deadly agency, keeps power lines far out of reach. This is explained by the fact that this particular kind of application of power to moving machinery requires the use of trailing cable instead of the more permanent type of construction that permits a moving contact, such as a trolley. The cables are designed to insulate fully the enclosed power lines against damage and loss of current; and employees are taught to handle them carefully, although engineers are not satisfied that the trailing cable is foolproof and are seeking constantly to improve methods and equipment to insure greater safety. In some sections they rely mainly on the construction of the cable and perfection of equipment, while in others additional precautions are taken, such as handling the cable with rubber gloves, slings, tongs, or loops. In some sections no temporary repairs are made to cables, while in others such repairs are made and later are vulcanized in the shop. At some operations the cycle of shovel duties is arranged so that cables are very seldom exposed to flying rock fragments while at others this exposure appears to be unavoidable. Methods of fastening the cable to the shovel frame and transporting the loose cable vary. Inspection and care of the cable are important in insuring its safety and durability. A limited amount of information was obtained by field engineers of the United States Bureau of lines from operators in various parts of the United States, as methods of handling electric-shovel operations differ with the districts; practices followed and equipment used in these districts are described in this circular.

Jan 1, 1936

By L. H. Banning

In the fall of 1953 the Philippine Bureau of Mines, under a Foreign Operations Administration Technical Assistance (FOA-TA) program, began a systematic investigation of the nickel content of the well-known Surigao laterite areas, on the island of Nonoc northeast of Mindanao, to determine the occurrence, distribution, and grade of nickel contained in the laterite and in the subjacent serpentine. At the same time, a technical review of the possibility of producing commercial ferronickel from the nickeliferous materials in the Philippine Islands was made, and a smelting process was suggested. The proposed process would be similar to that developed by the Federal Bureau of Mines for the reduction of the nickeliferous serpentine occurring in the Nickel Mountain ?deposit at Riddle, Oreg. The potential avail-ability of electric power from the Maria Cristina facilities at 3 mils per kw.-hr. would enhance the economic possibility of this program. Development of an economically feasible process for recovering nickel from the nickeliferous serpentines and laterites should lead to the establishment of a new industry in the Philippines, to the development of a source of nickel in the Far East, of which at present there is none, and to partial solution of the problem of supplying the free world with nickel. Enough preliminary reconnaissance had been completed by early 1954 to permit sampling of the deposit for metallurgical investigations. The FOA then requested the Federal Bureau of Mines Northwest Electrodevelopment Laboratory, Albany, Oreg., to conduct preliminary electric smelting studies on nickeliferous serpentine and laterite samples.

Jan 1, 1955

By G. S. Scott, G. W. Jones, I. Spolan, R. E. Kennedy

In studies made by the United States Bureau of Mines to determine the causes of explosions in medium-pressure acetylene generators , it was shown that when these are operated at elevated temperatures the acetylene liberated in an acetylene generator carries enough water vapor to heat certain types of carbides to a high temperature , when the acetylene- water vapor mixtures are passed through the carbide . This report contains results of further work carried out to develop an apparatus to show the heating effects or reactivity of various types of carbides in contact with acetylene - water vapor mixtures .

Apr 1, 1947

By Peter F. Steidl

Seven degasification wells have been completed in the Pittsburgh coalbed at the new Emerald mine near Waynesburg, Pa. Funding was provided by the Bureau of Mines to perform stimulation treatments on five of the wells, to show that this is a feasible and economical means of degasifying part of a coalbed. The seven wells ranged in depth from 590 to 910 feet. Stimulation treatments used 25,260 to 42,660 gallons of foam and 7,400 to 12,800 pounds of 20/40-mesh prop sand. Pumping rates were 10.8 to 11.6 bbl/min and treating pressures were from 1,050 to 1,600 psig. On the day following stimulation, gas production ranged from a few hundred cubic feet per day to more than 100,000 cu ft/day.

Jan 1, 1978

By M. M. Fine

This Bureau of Mines report describes the theory, experimental procedures, and the results obtained to date in the development of the Bureau's process for magnetically roasting iron ores using scrap iron as a means of reduction. Since magnetic separation is an operational step common to magnetic taconite plants, the preliminary research studies emphasized only the novel magnetic roasting step. The studies included the use of automobile scrap, ferrous reductants such as borings and turnings, and prereduced pellets. Technical feasibility of the process was demonstrated both on a bench- and pilot-scale. Quality magnetic concentrates with recoveries of over 90 percent were obtained from a direct shipping ore containing 59.5 percent Fe and from fine grained semitaconites with about 30 percent Fe.

Jan 1, 1966

By H. C. Fuller

Depletion of iron ore in the Nation's large deposits has directed attention to other sources. One of these is the titaniferous iron ore of the Iron Mountain, Wyo., area. Tests were made to determine the feasibility of smelting this ore, which contains about 20 percent titanium dioxide (Ti02), in an electric-arc furnace to produce pig iron. Initial tests, which were made in a 30-pound-capacity induction furnace, demonstrated that the iron could be easily reduced to metal and that limestone was a suitable and effective flux. Larger scale tests then were made in a 50-pound-capacity electric-arc furnace to obtain the more detailed information necessary for the planned continuous operation of a still larger arc furnace. The principal facts determined by preliminary batch-smelting studies were that (1) 9 pounds of limestone flux was required for each 100 pounds of ore smelted, (2) expensive coke was not required because coal proved to be a satisfactory reductant (near stoichiometric carbon was optimum), and (3) overreduction, which produced a viscous slag, must be avoided.

Jan 1, 1961

By David T. Couillard

Task training is increasingly important in mining operations because of the ever-accelerating pace of technological innovations and the concomitant increasing complexity of mining equipment. This Bureau of Mines report describes two successful task training program In use in two open-pit taconite operations in northeastern Minnesota. The programs are different in approach, but both have improved safety and in- creased productivity while lowering costs. Methods of training both before and after passage of the 1977 Mine Safety and Health Act are described, and the impact of this act on task training at each operation is discussed. The report identifies four common principles that have contributed to the success of the two training programs and presents plans each operation has for improving future training through new technology.

Jan 1, 1984

By M. H. Kersten, G. A. Brady, Jerry W. Ramsey

Anthracite samples were oxidized with nitric acid to prepare products representing intermediate stages of oxidation . Similar oxidizing conditions affected different anthracites to varying degrees as characterized by peptization behavior with 0.1 N NaOH . Techniques used in attempts to separate and characterize the products included esterification , absorption spectrophotometry , sublimation , chromatography , electrophoresis , metal salt formation , and solvent extraction . Mellitic acid , either free or in the form of metallic salts , was identified in the acid- soluble products from 10 tests in which the anthracite was treated with nitric acid for periods varying from 24 to 1,000 hours . pentacarboxylic acid was also found in some products . Other benzene carboxylic acids were not present in amounts detectable by the methods used in this study . The acid- insoluble residue from nitric acid treatment varied significantly in solubility behavior toward different classes of solvents . The most effective ones tried included polar oxygenated solvents and pyridine . Infrared spectra of the extracted material indicated that similar compounds were extracted by the different solvents . Aliphatic amines and aniline peptized the residue and o- toluidine reacted with it . Organic material separated from the residue by peptization with dimethylformamide contained 1 percent ash , consisting of more than 50 percent zirconium .

Jan 1, 1964

By Thomas Mucho, Anthony Iannacchione

This marks the 100th year that the aggregate industry has been served by a national association. Of all the accomplishments this longstanding relationship has achieved, there is probably none greater than the progress made, in worker safety. Perhaps the best way to measure this success is to examine injury trends in the aggregate miner population. For example, in the first half of the 20th [ ] century, 16 quarry mining disasters (a "disaster" is an incident with five or more fatalities) claimed 157 miners between 1909 and 1952. The largest of these was the disaster at the Sandts Eddy Limestone Quarry near Allentown, Pa., on March 26, 1942, where 31 miners died of asphyxiation by fumes/explosion. Thankfully, no mining disasters have occurred in the aggregate industry since 1952. It is these kinds of information that help us characterize improvements in aggregate worker safety over the last 100 years.

Jan 1, 2003

By F. W. Lee

List of GEOPHYSICAL ABSTRACTS

Jul 1, 1932

By T. A. Henrie, E. K. Kleespies

Carbon reduction of rutile and ilmenite in nitrogen and ammonia atmospheres was studied as a method of preparing titanium nitride . Ammonia was a better nitriding agent than nitrogen . The contact between the solid reactants , carbon and rutile , was a prime factor in nitrogen atmospheres and was of lesser import in dissociated ammonia . The reduction process for conversion of rutile to the nitride required carbon . The nitriding of ilmenite- carbon mixtures produced titanium nitride and elemental iron .

Jan 1, 1964

By W. W. Roepke

The Bureau of Mines has developed an interactive computer program that enables mine operators and others to identify the effect of cut-ting system changes on relative dustiness at the face. The program, which simultaneously evaluates machine parameters, coal seam parame-ters, and operator-controllable parameters, was developed for use on any microcomputer using BASIC programming language. The program allows the user to change one or more of the cutting system parameters at a time to see how these changes affect relative dustiness. A complete program listing and flowchart are included along with operating in-structions and sample outputs. An example showing how to use the program is also included.

Jan 1, 1985

By Margaret E. Egan

Reliable fire detection is essential for both safe evacuation and containment or extinguishment. In order to increase reliability by reducing the number of nuisance fire alarms in underground mines that use diesel-powered equipment, the U.S. Bureau of Mines has developed a diesel-discriminating fire detector (DDD). It was designed to discriminate between smoke produced by a fire and the smoke-laden exhaust of a diesel engine. Experiments were conducted by the Bureau to compare the smoke detection capabilities of the DDD with those of conventional fire detectors in response to smoldering coal and conveyor belting. A comparison was made among the alarm times of a carbon monoxide (CO) detector with an alarm threshold of 5 ppm, a smoke detector with an optical density alarm threshold of 0.044 of', and the DDD with an alarm threshold of 0.025 V. The results show that the DDD will reliably detect developing coal and conveyor belt fires. The average time delay separating the DDD alarm from the first detector to alarm was 76 s for smoldering conveyor belt and 65 s for smoldering coal. The longest time delay between the response of the DDD and the first detector to alarm was approximately 120 s.

Jan 1, 1993

By G. A. Savanick

The Bureau of Mines has designed, fabricated, and field tested a water jet cutting device capable of perforating nonmetallic well casings for the purpose of completing or stimulating in situ uranium leaching wells. The device is lowered into the wellbore, where it issues a high-velocity water jet that penetrates either a polyvinyl chloride or fiberglass casing, cement, and from 1 to 4 feet into the surrounding uraniferous sandstone. The resulting perforations allow leaching solution to pass between the sandstone and the wellbore. This report describes the water jet perforator, tells how it is used, presents cost data, and discusses the results of laboratory and field tests. The tests were designed to (1) determine the optimum operating conditions for water jet perforation, (2) assess the effects of changes in these conditions, (3) evaluate the performance of the water jet perforator under actual conditions, and (4) compare this method with other methods of well completion. These tests showed that water jet perforation is superior to conventional well completion methods for selectively achieving communication between the well-bore and adjacent sand while maintaining sand control, for restoring permeability lost through wellbore damage, for stimulating poorly performing wells for completing wells with casings that have inside diameters as small as 2 inches, and for extending the effective well diameter.

Jan 1, 1981