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By F. W. Osterwald, C. R. Dunrud

A continuously recording seismic network was constructed in 1962 by the U.S. Geological Survey to locate epicenters and record incidence of bumps (bounces, rock bursts) that occur in the bituminous coal mines of the Book Cliffs coal field near Sunny-side, Utah. The coal is mined because of its value as coking coal, although these bumps may be a hazard to life and property. Daily records of tremors caused by bumps for 1 3/4 years indicate that a seasonal pattern, as well as a daily pattern, exists for the number of bumps that occur in a given period. Maxima occur in May and June and November and December. Marked increases at 5-day to 9-day intervals are superimposed on these seasonal maxima. The largest bumps commonly occur during seasonal maxima when the rate of occurrence suddenly decreases and the amplitude of the individual bumps increases. Knowledge of this pattern may lead to prediction of general locations and periods of increased hazard from bumps. Experience to date has shown that prediction of precise times and locations of hazardous bumps is not possible, and may never be; primarily because even a small bump can be a hazard to life and property. Some bumps or bump sequences are actually composites, consisting or two or more discrete bumps a few tenths of a second to a few seconds apart. Violent and spontaneous releases of coal and rock from faces, ribs and roofs of mines (termed bumps or bounces by miners) are a common hazard to life and property in the coal mines located in the Book Cliffs near Sunnyside, Utah (Fig. 1). These bumps

Jan 1, 1965

By William H. Spice

The fault zone of south central Texas showed renewed activity during I940 along a trend roughly paralleling the old established Balcones fault-line group of producing fields. This was a result of the new discoveries in the Wilcox (Eocene) formation in southeastern Texas and Louisiana. As of the end of the year, one new field producing from the Wilcox formation had been discovered on the Washburn ranch in La Salle County, along the southwestern limits of the district, and several projected tests into that formation were under way. In the western part of the district, par-titularly in the part of the Rio Grande embayment that is in Dimmit, Webb and Zavala Counties, there has been renewed leasing activity with the shallower sands in the Navarro-Taylor formations (Upper Cretaceous) as the objective in several projected tests for the early part of 1941. Three new fields have been discovered along the old fault-line trend, but these have been comparatively small, producing either from Dale lime, Austin chalk or Buda lime. No new fields were discovered during the Year in the Edwards (Lower Cretaceous) lime horizon. Approximately 260 wells were drilled in the district during 1940, which resulted in four new oil fields. Twenty-seven new wells were completed in the Proven Edwards lime fields of Darst Creek, Luling and Salt Flat and seven were added to production in the Pearsall field. Approximately 160 wells in 18 counties were completed as failures during the year. The district produced 7,659,634 bbl. during 1940, which was a 9 per cent decrease under production for 1939. In all, 3559 wells were producing at the end of I940, compared with 3562 wells producing at the end of the previous year; 104 new producing wells were completed and 163 wells were abandoned in the producing fields of the district. During 1940 considerable exploratory work was carried on along the Wilcox trend within the district, particularly by major companies employing various types of geophysical methods, and leasing activity increased considerably. At the end of the year, the total number of acres of nonproducing leases held by major companies in the district increased about 10 per cent. It is anticipated that this activity will continue into the first part of 1941 and will be supplemented by several exploratory test wells. New Fields B,, Creek, Caldwett County.— . R. Ogden NO. 2 Talley, discovery well of the Bee Creek field, in the northeastern part of Caldwell County, was completed on March 16, I940, in Dale lime from 2091 to 2238 ft., pumping 85 bbl. per day, 39° A.P.1. gravity. The discovery of this field can be credited to a combination of subsurface geology and magnetometer work, which indicated the presence of a serpentine intrusion. At the end of the year, ,3 producing oil wells had been completed and the field has produced a total of 47,050 barrels.

Jan 1, 1941

By William H. Spice

The fault zone of south central Texas showed renewed activity during I940 along a trend roughly paralleling the old established Balcones fault-line group of producing fields. This was a result of the new discoveries in the Wilcox (Eocene) formation in southeastern Texas and Louisiana. As of the end of the year, one new field producing from the Wilcox formation had been discovered on the Washburn ranch in La Salle County, along the southwestern limits of the district, and several projected tests into that formation were under way. In the western part of the district, par-titularly in the part of the Rio Grande embayment that is in Dimmit, Webb and Zavala Counties, there has been renewed leasing activity with the shallower sands in the Navarro-Taylor formations (Upper Cretaceous) as the objective in several projected tests for the early part of 1941. Three new fields have been discovered along the old fault-line trend, but these have been comparatively small, producing either from Dale lime, Austin chalk or Buda lime. No new fields were discovered during the Year in the Edwards (Lower Cretaceous) lime horizon. Approximately 260 wells were drilled in the district during 1940, which resulted in four new oil fields. Twenty-seven new wells were completed in the Proven Edwards lime fields of Darst Creek, Luling and Salt Flat and seven were added to production in the Pearsall field. Approximately 160 wells in 18 counties were completed as failures during the year. The district produced 7,659,634 bbl. during 1940, which was a 9 per cent decrease under production for 1939. In all, 3559 wells were producing at the end of I940, compared with 3562 wells producing at the end of the previous year; 104 new producing wells were completed and 163 wells were abandoned in the producing fields of the district. During 1940 considerable exploratory work was carried on along the Wilcox trend within the district, particularly by major companies employing various types of geophysical methods, and leasing activity increased considerably. At the end of the year, the total number of acres of nonproducing leases held by major companies in the district increased about 10 per cent. It is anticipated that this activity will continue into the first part of 1941 and will be supplemented by several exploratory test wells. New Fields B,, Creek, Caldwett County.— . R. Ogden NO. 2 Talley, discovery well of the Bee Creek field, in the northeastern part of Caldwell County, was completed on March 16, I940, in Dale lime from 2091 to 2238 ft., pumping 85 bbl. per day, 39° A.P.1. gravity. The discovery of this field can be credited to a combination of subsurface geology and magnetometer work, which indicated the presence of a serpentine intrusion. At the end of the year, ,3 producing oil wells had been completed and the field has produced a total of 47,050 barrels.

Jan 1, 1941

By C. A. Stetefeldt

The purpose of this paper is to convince the managers of silvermills that their customary reports in regard to the percentage of silver saved are far from the truth. It may be unpleasant for them to have the proofs of this fact brought before the public, and for this rezson the author refrains from giving the names of the mines and mills from which the statistics here recorded were obtained. It may be asked: What is gained by informing the stockholders of our silver-mines that they receive incorrect reports? Will this increase their dividends or lessen their assessments? In the first place, it is always better to publish honest facts than fiction. In the second place, many superintendents believe in the correctness of their reports, and have no idea how much they deceive themselves. Finally, the knowledge that hitherto unexpected losses of silver take place may lead to the adoption of methods by which these losses are greatly reduced. These remarks refer also to smelting-works. The present paper, however, is concerned exclusively with amalgamation and lixiviation. The first and most important error is found in the inaccuracy of the commercial assay; the second in the incorrect sampling of tailings in amalgamation. Further, mills not doing custom-work, but reducing exclusively ores from mines to which the mills belong, are in the habit of weighing the ore only approximately and without making moisture-tests. Thus, a correct basis for calculating the actual percentage of silver extracted is lacking. The superintendent, then, finds it convenient to report the apparent extraction, i.e., the extraction indicated by comparing the value of the roasted ore, minus soluble salts, with the value of the tailings. How many errors are thereby committed it is not necessary to point out.

Jan 1, 1895

By W. E. C. Coxe

Many of you who are interested in the manufacture of iron and steel, have no doubt heard of the "Wheeler process for combining iron and steel." Mr. Wheeler has formed a company, styled the "Combination Trust Company," whose business is to grant licenses for the use of this patent process in producing what he calls "iron-clad steel." It has been proposed to apply it in the manufacture of car or wagon axles, also to shafting, having steel cores or centres covered with iron; to tubes of steel with an inner and outer skin of iron ; to structural purposes, such as girders and beams; bridge and tie-bolts, where the strength of the iron and the rigidity of the steel would be desirable. In answer to a request from Mr. Wheeler, permission mas accorded him to make some experiments at the rolling mill of the Philadelphia and Reading Coal and Iron Company, at Reading, Pennsylvania, with a view to manufacturing some steel-headed rails. In making this kind of a rail two difficulties are encountered. If the iron is brought to the requisite heat to weld properly, the steel is likely to be burned; if the steel is cared for, to prevent burning, the several layers of iron are not brought up to the proper welding heat. Mr. Wheeler claimed that the steel slab covered with iron which he furnished for the head of the rail could net be injured by any heat to which it might be subjected in the ordinary course of heating the rail-pile. He claimed, also, that by this method the porosity, which he thought was characteristic of all solid rails of Bessemer steel, would be overcome. Four steel slabs were furnished for this experiment, being Bessemer steel of .61 carbon, made at the Edgar Thomson Steel Works, and covered with iron in one of the Pittsburgh mills. The slabs were in section seven inches wide by three inches thick, and the iron covering was one-eighth to three-sixteenths inch thick. Each slab was placed on a pile of iron made up in the ordinary way for a rail fifty-six pounds per yard and thirty feet long. The heating was under the personal direction of Mr. Wheeler, and

Jan 1, 1879

By B. H. Sage, W. N. Lacey, W. M. Morris

The volumetric behavior of isobutane at temperatures below its critical temperature has been studied by several investigators. Seibert and Burrelll measured the vapor pressure of isobutane from the ice point to the critical temperature. Dana and co-workers2 determined among other thermodynamic quantities the density of the saturated liquid and the saturated gas and the vapor pressure from approximately 0 to 130 F. Sage and Lacey3 studied a number of the thermodynamic properties of this hydrocarbon from 70" to 250" F. The specific volume in the gas and liquid region was determined at pressures up to 3000 Ib. per sq. in.? throughout this temperature interval. In addition, the vapor pressures were measured at 30" intervals. These data taken together serve to establish the thermodynamic behavior of isobutane at temperatures between 0" and 250" F. with reasonable accuracy. However, apparently there are no data available at the higher temperatures. For this reason an investigation of the volumetric behavior of isobutane at temperatures between 100" and 460" F. was carried out with apparatus that has been described in another paper (p. 136, this volume). Materials The isobutane used in this investigation was obtained from the Philgas Division of the Phillips Petroleum Co. That company's special analysis upon this sample indicated it to contain less than 0.03 mol per cent of impurities. In order to avoid traces of noncondensable gases, this hydrocarbon material was subjected to two successive fractionations at a high reflux ratio in a column approximately 4 ft. long and % in. in diameter, which was packed with small glass rings. The middle portion of distillate from the first fractionation was used in the second fraction-ation and a portion of the overhead from this second distillation process was repeatedly condensed at liquid-air temperatures at a pressure only slightly above the sublimation pressure of isobutane at this temperature.

Jan 1, 1940

By W. N. Lacey, B. H. Sage, W. M. Morris

The volumetric behavior of isobutane at temperatures below its critical temperature has been studied by several investigators. Seibert and Burrelll measured the vapor pressure of isobutane from the ice point to the critical temperature. Dana and co-workers2 determined among other thermodynamic quantities the density of the saturated liquid and the saturated gas and the vapor pressure from approximately 0 to 130 F. Sage and Lacey3 studied a number of the thermodynamic properties of this hydrocarbon from 70" to 250" F. The specific volume in the gas and liquid region was determined at pressures up to 3000 Ib. per sq. in.? throughout this temperature interval. In addition, the vapor pressures were measured at 30" intervals. These data taken together serve to establish the thermodynamic behavior of isobutane at temperatures between 0" and 250" F. with reasonable accuracy. However, apparently there are no data available at the higher temperatures. For this reason an investigation of the volumetric behavior of isobutane at temperatures between 100" and 460" F. was carried out with apparatus that has been described in another paper (p. 136, this volume). Materials The isobutane used in this investigation was obtained from the Philgas Division of the Phillips Petroleum Co. That company's special analysis upon this sample indicated it to contain less than 0.03 mol per cent of impurities. In order to avoid traces of noncondensable gases, this hydrocarbon material was subjected to two successive fractionations at a high reflux ratio in a column approximately 4 ft. long and % in. in diameter, which was packed with small glass rings. The middle portion of distillate from the first fractionation was used in the second fraction-ation and a portion of the overhead from this second distillation process was repeatedly condensed at liquid-air temperatures at a pressure only slightly above the sublimation pressure of isobutane at this temperature.

Jan 1, 1940

By A. W. Demmler

RECENTLY, Chaudron,&apos; Montariol,2 and their co-workers published the results of their studies on zone-refined aluminum. They found their material to be capable of recrystallization at —50°C, but gave no data as to the percentage reduction or time required. Their material was found to be practically non-work hardening at room temperature, but after 96 pct cold work at a low temperature and storage in liquid nitrogen it was found to recrystallize to coarse grains in less than 3 hr at 20°C. Recently, a study was made of the room temperature recrystallization characteristics of zone-melted aluminum. An ingot 14 in. in length, with a 3hx3 in. cross section, was made in an extremely high purity graphite boat under an atmosphere of dried commercial argon. It was made by first passing the molten zone along the ingot of 99.99+ pct A1 15 times. At this point, the most impure 3 in. (the end toward which the eutectic forming impurities migrated) were replaced with more of the original starting material, and 15 more traverses were made. Each traverse of the zone along the ingot required approximately 3 hr. Three ingots were prepared in this identical fashion and the chemical analyses were made spec-trographically on two of these ingots, rather than on the one used in this investigation. The analyses were made at 1 in. intervals along the ingot, in duplicate. Over the purest 5 in. of the ingot, which were most important in this investigation, there was found an average composition of <0.00004 pct Cu, <0.0003 pct Fe, <0.0001 pct Si, and <0.0001 pct Mg. In addition, the following elements were not detected spectrographically even in the more impure end of the bar: manganese, zinc, nickel, chromium, titanium, vanadium, lead, tin, boron, beryllium, bismuth, gallium, zirconium, cadmium, antimony, cobalt, and molybdenum. The original ingot was given several cold reductions, with intermediate anneals in order to refine the grains. Owing to the extreme length resulting and the ease of deforming the material plastically, it was cut into eight equal lengths and identified as shown in Fig. 1, with the highest numbered section at the purer end (that enriched with peritectic formers). Section 6 was used in the exploratory work and was found to be of exceptionally high purity, giving more rapid rates of room temperature re crystallization than any previous aluminum studied at the Alcoa Research Laboratories. This fact suggested that the entire midsection of the ingot might be of very high purity. Accordingly, section 4 was chosen for the next study. A portion of it was rolled to cold reductions of 10, 25, 40, 60, 75, and 90 pct at room temperature, and the re-crystallization of each specimen was followed by X-ray pinhole transmission photographs. The other portion received the same treatment, except that both the specimens and the rolls were maintained at 160°F in the process of rolling. The latter ortion was retarded in its recrystallization as compared to the former, probably due to the stress relief effect of the warm rolling. Both of these portions of the fourth section were found to recrystallize at a considerably slower rate than did the sixth section.

Jan 1, 1957

By AIME AIME

THE complete list of papers for the meeting of the Petroleum Division that is to be held" at Tulsa,&apos; Thursday and Friday, Oct. 3 and 4,, with assignment to individual sessions is given below. THURSDAY MORNING First Session Well Spacing Theory of Well Spacing-By W. P. Haseman. Discussion by S. C. Herold, J. R. Suman and Lester C. Uren. Well Spacing in the Long Beach Field, California-By - Stender Sweeney. Discussion by C. H. McNeese; R. R Brandenthaler and W. V. Vietti. Well Spacing in the Bradford Field, Pennsylvania-By Paul D. Torrey. Discussion by A. F. Melcher, R. M.. Haskell, J. B. Umpleby and J. B. Newby. Results of Different Well Spacing in the Salt Creek Field, Wyoming-By Fred E. Wood. Discussion by Sam Grinsfelder and Kenneth B. Knowles.

Jan 1, 1929

By R. C. Ellman

In the United States, the consumption of lignite and subbituminous coals is increasing. A variety of energy-oriented companies have leased large blocks of reserves, new large power plants are in operation and being constructed, and new producing mines are being developed. The Bureau of Mines has maintained an active interest in the utilization of low-rank coals for many years. In 1951, with the completion of the Bureau&apos;s Grand Forks Coal Research Laboratory, an organizational unit was established for studies in lignite preparation. Since that time, numerous investigations have been completed. This research has dealt almost exclusively with lignite, but since subbituminous coals have many similar characteristics, the findings can often be applied to both types of coal.

Jan 1, 1970

By John C. Gifford, Charles L. Thomas

A unique and reproducible method is presented for the determination of water vapor in tough pitch wire bar copper. The procedure involves reduction of the water vapor with molten aluminum to form hydrogen, which is subsequently measured by mass spectroscopy. Average water vapor pressures within the porosities of the wire bar samples are calculated. Correlation is to exist between the specific gravities of the samples and their measured water vapor contents. The method should find application as a very sensitive means of detecting hydrogen embrittlement in copper. The nature and quantity of gases evolved and retained during the horizontal casting of tough pitch wire bar copper have long been of interest to the metallurgist. Considerable work has been done at this laboratory on the determination of these gases. The work has involved not only qualitative but also quantitative analysis, so as to provide a basis for a total accounting of the porosity which is associated with the cast product. From a knowledge of the gas-forming elements within the copper, and the practice of melting and protecting it with a reducing flame followed by contact with a charcoal cover in the casting ladle, the gases which one might expect to find in the pores of the cast product are sulfur dioxide, carbon monoxide, carbon dioxide, hydrogen, and water vapor. Hydrogen sulfide, nitrogen, and hydrocarbons would be other possibilities; however vacuum fusion-mass spectroscopy techniques employed at this laboratory have shown that no hydrogen sulfide and only traces of nitrogen and methane are present. It is highly improbable according to phillipsl that any sulfur dioxide could be evolved in wire bar copper with 10 ppm or less sulfur under normal freezing conditions. Mackay and smith2 have noted that porosity due to sulfur dioxide only becomes noticeable at concentrations above 20 ppm S. Investigation of carbon monoxide and carbon dioxide by a variation in the method of Bever and Floe showed that these two gases could only account, at 760 mm and 1064°C (Cu-Cua eutectic temperature), for a maximum of about 25 pct of the total porosity in a wire bar having a specific gravity of 8.40 g per cu cm. phillips&apos; has noted that no normal furnace atmosphere is ever sufficiently rich in hydrogen to cause porosity in copper from hydrogen alone. In addition, using a hot vacuum extraction technique for hydrogen,4 values have never been observed in excess of 10 ppb in tough pitch wire bar. On the basis of the preceding considerations of gases in tough pitch wire bar, only water vapor is left to account for the major portion of the porosity. Direct determinations of water vapor are virtually impossible at low concentrations by any presently known technique, due to adsorption and desorption within the walls of the apparatus used.5 The present investigation deals with a method for the determination of water vapor by an indirect procedure, using molten aluminum as a reducing agent to form hydrogen according to the reaction: 2A1 + 3H2O — A12O3 + 3H2 The evolved hydrogen can then be measured quantitatively by mass spectroscopy. EXPERIMENTAL A 10-g piece of 99.9+ pct A1 was charged into a porous alumina crucible (Laboratory Equipment Co., No. 528-30). Fig. 1 shows the crucible in place at the bottom of an 8-in.-long quartz thimble. A funnel tube with two l1/8-in.-OD sidearms extending at a 90-deg angle from each other was attached to the top of the thimble. One of the sidearms was joined to the inlet system of the mass spectrometer (Consolidated Electrodynamics Corp. Model 21-620A) via a mercury diffusion pump situated between two dry-ice traps. The copper samples were placed in the other sidearm, followed by a glass-enclosed magnetic stirring bar for pushing the samples into the crucible. All ground joints were sealed with vacuum-grade wax. The entire system was evacuated and the aluminum was heated with a T-2.5 Lepel High Frequency Induction Furnace for 21/2 hr at a temperature visually estimated to be 900°C. The temperature was then lowered and the hydrogen was monitored on the mass spectrometer until it was given off at a constant rate of about 4 to 5 1 per hr. This rate corresponded to a slope of 2 to 3 divisions per min on the X3 attenuation of a 10-mv recorder at a hydrogen sensitivity of approximately 100 divisions per 1. A micromanometer (Consolidated Electrodynamics Corp. Model 23-105)

Jan 1, 1969

By Elmars Ence, Harold Margolin

A. J. Goldak and J. Gordon Parr (University of Alberta) —While we appreciate the difficulties involved in any investigation of this system, and we wish to congratulate the authors on their comprehensive efforts, there are several aspects of their paper that are not clear to us. 1) If the 6 phase is, in fact, isomorphous with Ti3Sn, it should not be designated Ti,Al. An 4B structure cannot be isomorphous with an ordered structure of the DO type. Anderko et al.&apos; suggested that the structure be called Ti3A1, and we believe this to be a more reasonable designation. The confusion is compounded when the authors designate the phase Ti3Al—yet the composition limits of this phase (according to their diagram) are approximately Ti,A1 and Ti,Al. Further, while Pietro-kowsky is said to have pointed out that the structure of the 6 phase is isomorphous with Ti3Sn, we understand that this was only a suggestion that was not confirmed. Margolin and Ence do not appear to have presented any evidence to support the suggested isomorphism. 2) In referring to the precipitation observed microscopically during the initial breakdown of high A1 a during quenching, the authors state that "such precipitation is not likely to be detected by Debye-Scherrer techniques". We suspect that if the precipitate was visible by optical microscopy, it must have at least one dimension of the order of 1 or greater, and would therefore be readily detected by diffraction techniques. 3) The authors state: "The basis for this suggestion (that 6 forms peritectically P + L—6) is the observation that the ,&apos;3 + 6 and 6 phase fields were

Jan 1, 1962

By H. E. Stauss

THE time-to-fracture test has been applied to pure platinum and to two alloys of platinum under the special conditions of small cross-sectional area of the specimens and of a test temperature above the annealing temperature. While the results are similar in character to those secured with large specimens of steel at temperatures below the annealing temperatures, two differences are noted: (I) an upward inflection in the curves for log stress vs. log time for the alloys, and (2) a sharp break in the curve for log stress vs. log time for pure platinum when single crystals filled the wire. The experiments showed that: (I) platinum and 10 per cent rhodium-platinum maintained their strengths at 1100°C. better than did 10 per cent iridium- platinum, and (2) the rhodium-platinum after a time exceeded the iridium-platinum in strength at 1100°C. Platinum alloys in their service at high temperatures encounter conditions some- what similar to those that exist in the usual form of the time-to-fracture "l test with steel. This paper is intended primarily to present results obtained by a "time-to- fracture" test under conditions approximating actual service for platinum (at the temperature 1100°C. under oxidizing conditions) with three materials, pure platinum (99.99 per cent), a platinum alloy with lo per cent iridium, and a platinum alloy with 10 per cent rhodium. The experimental procedure differed from that previously used in this type of measurement in that the samples were of small diameter (0.010 in.), were fully annealed, and were tested at a temperature definitely above their annealing points (600°C., 1000°C. and 1050°C., respectively, for 60 per cent cold reduction and 15 min. heating time2,3). The experimental arrangement was similar to that previously described,4 using as heating unit a small, horizontal, platinum- wound furnace, ½ by 12 in., maintained at constant temperature by an automatic controller. The samples were 0.010-in. wires, which had been annealed at 1200°C. by drawing them slowly through the furnace. The time-to-fracture was measured electrically. Elongation was not determined because of the difficulties inherent in the experimental arrangement. Life-that is, the time-to-fracture-was considered the important property in these first tests. No attempt was made to measure the reduction in area, but the types of fracture were noted qualitatively; in the text they are referred to as (I) the normal, plastic, or necked fracture, (2) the knife-edge fracture, and (3) the brittle or intercrystalline fracture with small reduction of area. Results for different constant applied stresses are plotted in Fig. I. In all cases at least two trials were made for each stress, although they cannot always be indicated separately on the curves. The breaking stresses drop very rapidly to a small frac-

Jan 1, 1943

By E. S. Bardwell

Each of the three refining furnaces in use at Great Falls is provided with a waste-heat boiler. The general arrangement of furnace and boiler is as shown in Fig. 1. Two of the furnaces have hearths 45 ft. 7 in. by 14 ft. 6 in.; the third has a hearth 46 ft. 101/2 in. long and of the same width as the other two. The furnaces at present are equipped for firing with natural gas. As originally constructed two of the furnaces had hearths 36 by 14 ft., and were designed to use coal on grates, but these furnaces were lengthened and fired successively with pulverized coal and oil. The third furnace was added in 1926 and was oil-fired until 1928. Since that year natural gas has been in use on all of the furnaces. The changes that have occurred in connection with furnace design and the comparative performance of the furnaces with various fuels were described1 by the author in 1932. Two of the furnaces are provided with Stirling class A-30 boiler. rated at 400 hp. and having 4008 sq. ft. of heating surface. The thir furnace has a class A-21 Stirling waste-heat boiler rated at 300 hp. with 2805 sq. ft. of heating surface. The boilers are not baffled. The waste-heat boilers are placed on a platform 17 ft. 3 in. above the level of the furnace charge floor. The waste gases from the furnace pass by a vertical uptake flue, 4 by 3 ft. inside at the point where it enters the chamber, to a brick chamber from which the gases pass over a bridge wall and into the boiler setting. The uptake flue and chamber are constructed of silica brick. Each furnace has a steel stack 125 ft. high, measured from the boiler floor. The stacks have a 41/2-in. firebrick lining and are 5 ft. in diameter

Jan 1, 1934

The 112th Meeting of the Institute, and the Annual Business Meeting, will be held at the Headquarters of the Institute in New York City, Feb. 14 to 17, 1916. The Chairmen of several of the technical committees report that papers on subjects of timely interest in their respective branches have been promised. David H. Browne, who was appointed Chairman of the Committee on Arrangements, has organized his committee for active work. Members are urged to make their plans now to be present at this meeting to avail themselves of the pleasant opportunity for greeting old friends and making new ones among those engaged in the same profession.

Jan 12, 1915

By William Meyer

DURING the seventeen years Fairchild has been making aerial surveys and aerial photographic equipment many changes and improvements have been made in the equipment and in the technique of using it. Aerial photographic operations have, been developed from the crude methods and apparatus of wartime to a science upon which exact engineer-ing calculations can be based. In the early days there was no airplane specially designed to meet aerial photographic requirements. One type of camera was used in all types of operations. Projects were made to conform to the products we could make and deliver. Obviously this entailed definite limitations. We now have airplanes designed specially for aerial photographic operations in accordance with the conditions encountered in actual service experience. We have cameras for every photographic purpose and our laboratory technique and equipment have been developed to the point where it is possible to make contour maps from vertical aerial photographs with contour intervals as close as five feet. Therefore, the selection of equipment now can be made in accordance with the time at our disposal, the justifiable cost, the scale desired, and the general requirements of the client. This does not mean, however, that arbitrary deliveries can be set for aerial photographic products. The factors in each project vary and each job must be considered in accordance with the factors involved. This accounts for the fact that products of aerial surveys may readily vary from $1.25 to $200 a square mile. Sherman M. Fairchild became interested in the design of a radically different aerial camera during the war. At its close he was about ready to demonstrate his design to the War Department. By 1920, he was able to bring out his first completed model. It had a number of radical features, one of which was the first dependable high-speed between-the-lens shutter, which makes for accuracy in aerial photographic work. Another feature was the use of metal throughout, eliminating the wooden parts that had been employed in wartime cameras. Another feature was the interchangeability of parts.

Jan 1, 1936

By -1ng. B. Stampa

Introduction The author investigates the technology available for mine flow reversibility by reversing the operation of the main fans. Air bypassing, reversed sense of impeller rotation, and blade angle overturning are indentified as the most important means of achieving the flow reversibility. The axial flow fan is studied in some detail and the important variables of fan capacity, pressure, and efficiency are compared. Although some references to rotor velocity vectors are made (Fig. 1) the subject is not presented in detail in order to stay within the paper&apos;s intent. Background Where applicable, the requirements of mine air reversibility are an important part of the overall mining operation and should be given proper attention during mine ventilation design. The need for preventing mine fires in intake shafts is the reason that, for a long time, it has been a requirement in the Eastern European countries to have the feature of flow reversibility built into all main mine ventilators. In West German coal mines, this requirement does not apply since higher priority is given to safety precautions. Some metal and mineral mines in the United States are required to have ventilation currents readily reversible in order to fight underground fires as stipulated by the Title 30, Mineral Resources, and by the mining laws of some states. From an equipment performance standpoint, assuming the validity of other flow technical data, the question of the ventilator flow reversibility is of ten related to the actual scenario of the begining of an emergency. Most of the time, the system operates within half of the design capacity only and assuming that the equivalent mine orifice is stable only a quarter of the design pressure must be produced by the fan in any event. For such an operating point, the effective gradient and energy losses can be disregarded since fire emergencies usually last for only a short period of time. Equipment Comparison Fig. 2 depicts a ventilation arrangement wherein the flow can be reversed through changing the functional position of the dampers (slideplate or blade type). Both axial or radial fans can be applied in this case. For the mine exhaust operation, slide plates (guillotines) I and I11 are opened while plates I1 and IV are closed. The flow thus encounters two reroutings, which due to the reverse ventilation flow cannot be equipped with proper sheet metal deflectors, and therefore large pressure losses result during the air reroute operation. When the intake operation is considered, the dampers I and I11 are closed and the pair I1 and IV is opened. For this arrangement, almost the same flow conditions exist as for the foregoing exhaust mode; however, one additional corner must be applied. Even if a highly efficient ventilator is used in one of the previously described systems, the additional pressure losses resulting from air rerouting plus those encountered between the planes "0" and "00" significantly affect the overall energy requirements. Illustrated in Table 1 are the relative component losses of even flows for evaluation of various detour arrangements. From the aerodynamics standpoint, when these components are being designed, serious consideration must be given to the individual levels of the pressure loss coefficient, 5. Should there be an increase in the sum of the loss coefficients due to the particular component selection such that, for example, the net change is 1.2; the resulting pressure to be produced by the fan can be calculated from:

Jan 1, 1981

By P. G. Shewmon

THIS paper is concerned with the redistribution of a second phase when a 2-phase solid alloy is annealed in a temperature gradient. An examplewhich is discussed in detail is the redistribution of carbides in a low-carbon steel annealed in a temperature gradient below the A, temperature. As a result of such a treatment, the carbides at the cooler side disappear, while those at the hotter side grow in size. In a 2-phase zirconium-hydrogen alloy, the amount of hydride will tend to be increased at the cold end and decreased at the hot end. That such an effect can occur in solid metals is not generally appreciated. However, with the trend toward higher operating temperatures in several fields, this phenomenon will become more important in the future. Actually, such effects should be rather common in the core of nuclear power reactors where the op- erating temperatures are high and temperature gradients are an order of magnitude higher than in previous high-temperature applications of alloys. The purpose of this paper is to point out the existence of such an effect, to discuss the manner in which one predicts whether a redistribution of the second phase will occur in a given system, whether the second phase will go to the hot or cold face, and how rapidly the redistribution will occur. One aspect of this problem has been discussed by pfam and Wernick2who considered the migration of a small liquid region through a solid. In their case, the diffusivity in the liquid is much larger than in the solid and they have interpreted their results successfully by using Fick&apos;s first law as the flux equation in the liquid, and taking the concentration gradient from the phase diagram. For all the cases they have studied, this type of analysis predicts that the liquid region migrates from the cold end to the hot end, and this is what was found ex-

Jan 1, 1959

By Norman F. Schulz, Emert W. Lindroos, Strathmore R. B. Cooke

DURING the course of an investigation of the effects of various starch products on hematite and quartz in regard to their separation by flotation, it was found that whereas most starches flocculated suspensions of hematite in water, they did not flocculate similar suspensions of quartz. However, a derivative of whole corn starch containing approximately one tenth aminoethyl group (-—CH,CH2NH2) per glucose unit proved to be an exception. This aminoethyl starch was a very good flocculant for both hematite and quartz, and also possessed the property of depressing both minerals in cationic flotation tests. In view of the widespread use of starch as a flocculating agent of solids in tailing water, pulps, and for coal slimes, ore and various other purposes in sulphide and nonsulphide flotation, attention is called to the effective surface activity of aminoethyl starch in flocculating suspensions of the two minerals investigated. Test Materials The starch products employed included Globe Pearl starch No. 144 and fresh aminoethyl starch, both supplied by the Corn Products Refining Co. Dr. A. L. Elder" has kindly furnished a description The minerals used in the various tests are listed in Table I. Their specific surfaces were determined by the air permeability method, which gave results reproducible to within plus or minus 3 pct. Surface areas obtained by krypton adsorption were greater than the air permeability values by a factor of 2.0 for quartz and 62.4 for hematite. Starch Adsorption on Mineral Surfaces Starch adsorption data were obtained by agitating for 1 hr measured volumes of neutral starch solutions of known concentrations with weighed quantities of finely divided mineral of measured specific surface. The mineral then was separated from the pulp liquor by centrifugation and the residual starch content determined by chemical analysis. The analytical procedure consisted of oxidizing the starch with an excess of dichromate in acid medium at elevated temperature and titrating the excess dichromate by the ferrous ammonium sulphate—potassium permanganate method. Analytical results were reproducible to within less than 1 pct. Adsorption data obtained in unbuffered solutions near the neutral point are plotted in Fig. 1. The adsorption on either mineral was far greater for the aminoethyl starch than for the Pearl starch. Flocculation The degree of flocculation was determined for a given pulp by measuring the time required for the supernatant liquid to reach a certain degree of clarity. This was accomplished by passing a standard light beam through the pulp, contained in a glass settling tube, and measuring the time required after agitation ceased for the intensity of the transmitted beam to reach a predetermined value. Starch reagent was added to each pulp in small uniform increments, and the settling time was determined after each such addition. Increase in pulp liquor volume due to the added starch reagent was ignored in these tests. Pulps were maintained at or near neutrality. of the preparation of the aminoethyl starch: "Three hundred and sixty grams of powdered unmodified corn starch was slurried in 3 liters of water and stirred during gelatinization. Eighty-six grams of ethylenimine was added slowly during reflux which was continued for 4 hr. The yellow solution set to a gel upon cooling. This was broken up and neutralized with HC1. The thick paste was dried on hot rolls. Adsorbed polyethylenimine and salts were removed from the yellowish products by washing first with acidified aqueous &apos;60 per cent&apos; alcohol. The white product contained nitrogen corresponding to about one aminoethoxy group per ten glucose residues." Only laboratory samples of this starch derivative have been prepared. The starch reagents for use in flocculation, flotation, and adsorption tests were made up by dispersing the appropriate quantities of air-dry starch in cold water, adding boiling water, and heating for 30 min at 120°C under pressure. When used ip adsorption tests, the starch solutions first were cleared of insoluble matter by centrifugation.

Jan 1, 1953

By Strathmore R. B. Cooke, Emert W. Lindroos, Norman F. Schulz

DURING the course of an investigation of the effects of various starch products on hematite and quartz in regard to their separation by flotation, it was found that whereas most starches flocculated suspensions of hematite in water, they did not flocculate similar suspensions of quartz. However, a derivative of whole corn starch containing approximately one tenth aminoethyl group (-—CH,CH2NH2) per glucose unit proved to be an exception. This aminoethyl starch was a very good flocculant for both hematite and quartz, and also possessed the property of depressing both minerals in cationic flotation tests. In view of the widespread use of starch as a flocculating agent of solids in tailing water, pulps, and for coal slimes, ore and various other purposes in sulphide and nonsulphide flotation, attention is called to the effective surface activity of aminoethyl starch in flocculating suspensions of the two minerals investigated. Test Materials The starch products employed included Globe Pearl starch No. 144 and fresh aminoethyl starch, both supplied by the Corn Products Refining Co. Dr. A. L. Elder" has kindly furnished a description The minerals used in the various tests are listed in Table I. Their specific surfaces were determined by the air permeability method, which gave results reproducible to within plus or minus 3 pct. Surface areas obtained by krypton adsorption were greater than the air permeability values by a factor of 2.0 for quartz and 62.4 for hematite. Starch Adsorption on Mineral Surfaces Starch adsorption data were obtained by agitating for 1 hr measured volumes of neutral starch solutions of known concentrations with weighed quantities of finely divided mineral of measured specific surface. The mineral then was separated from the pulp liquor by centrifugation and the residual starch content determined by chemical analysis. The analytical procedure consisted of oxidizing the starch with an excess of dichromate in acid medium at elevated temperature and titrating the excess dichromate by the ferrous ammonium sulphate—potassium permanganate method. Analytical results were reproducible to within less than 1 pct. Adsorption data obtained in unbuffered solutions near the neutral point are plotted in Fig. 1. The adsorption on either mineral was far greater for the aminoethyl starch than for the Pearl starch. Flocculation The degree of flocculation was determined for a given pulp by measuring the time required for the supernatant liquid to reach a certain degree of clarity. This was accomplished by passing a standard light beam through the pulp, contained in a glass settling tube, and measuring the time required after agitation ceased for the intensity of the transmitted beam to reach a predetermined value. Starch reagent was added to each pulp in small uniform increments, and the settling time was determined after each such addition. Increase in pulp liquor volume due to the added starch reagent was ignored in these tests. Pulps were maintained at or near neutrality. of the preparation of the aminoethyl starch: "Three hundred and sixty grams of powdered unmodified corn starch was slurried in 3 liters of water and stirred during gelatinization. Eighty-six grams of ethylenimine was added slowly during reflux which was continued for 4 hr. The yellow solution set to a gel upon cooling. This was broken up and neutralized with HC1. The thick paste was dried on hot rolls. Adsorbed polyethylenimine and salts were removed from the yellowish products by washing first with acidified aqueous &apos;60 per cent&apos; alcohol. The white product contained nitrogen corresponding to about one aminoethoxy group per ten glucose residues." Only laboratory samples of this starch derivative have been prepared. The starch reagents for use in flocculation, flotation, and adsorption tests were made up by dispersing the appropriate quantities of air-dry starch in cold water, adding boiling water, and heating for 30 min at 120°C under pressure. When used ip adsorption tests, the starch solutions first were cleared of insoluble matter by centrifugation.

Jan 1, 1953