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By Robert M. Becker

This report (the second in a series of five) presents the mathematical development in extending the theory of sample reliability from a sample consisting of a fixed number of items to a sample consisting of a fixed amount of items. Examples of a fixed amount of items per sample are samples consisting of a fixed weight or a fixed volume of unequal size particles. The probability distribution functions (those here called the compound binomial and compound multinomial functions) are developed from fundamentals. Their distributions are generalized to include some measured characteristic of the items. Infinite population moments are derived from moment-generating functions, while finite population moments are developed from corresponding infinite population moments using the finite probability operator defined in part 1 of this series.

Jan 1, 1964

By H. R. Babitzke, H. Kato, R. E. Siemens, G. Asai

The purpose of this investigation was to develop a wide variety of columbium and tantalum alloys and to determine their suitability for use at elevated temperatures . Sixty - nine columbium and tantalum alloys were investigated . For this study , columbium was alloyed with two or more of the following : nium, tungsten , vanadium , titanium, and zirconium . Tantalum was alloyed with vanadium or hafnium, or hafnium and carbon . The fabricability was determined by an arbitrary procedure . Hardness measurements , elevated - temperature tensile properties , and oxidation- resistance studies were made . Of the alloys studied , Cb - 15 Hf - 5W, Cb - 15Hf - 5W- 10Ti , Cb - 15Hf - 10W- 10Ti , Cb - 10V - 5W, Ta - 30V , and Ta - 20 to 33Hf exhibited excellent high - temperature properties . These alloys were not only easy to fabricate , but they also had good oxidation resistance and excellent high- temperature strength .

Jan 1, 1964

By W. P. Haynes, A. J. Youngblood, J. J. Demeter

Synthesis of high - Btu gas , using the Fischer - Tropsch reaction was investigated in a tube - wall reactor of 2 - inch steel . The catalyst was carbonexpanded iron ( CEI ) , formed on the walls of a steel reactor by exposing the reactor to 1H₂ + 100 synthesis gas under certain conditions . Advantages to be gained from successful development of the CEI - coated tube- wall reactor are elimination of catalyst plant and catalyst handling and charging operations , high- temperature operation , and a relatively low- cost , reactor -heat recovery system . In one test ( TW- 8 ) in which the reactor was filled with CEI , the reactor was operated for 1,910 hours before the test was stopped because of excessive pressure drop caused by carbon deposition . The pressure drop was satisfactory for 1,000 hours of operation at an hourly space velocity of 300 , but it increased rapidly at space velocities of 600 and 1,000 . When operated at a space velocity of 300 , with a ratio of 1 to 1 recycle at 534 ° C , a conversion of 72 percent of the 3H + 100 synthesis gas was achieved . The product gas had a heating value of about 610 Btu per cubic foot and could be suitably upgraded to 900 - Btu gas by subsequent use of a nickel catalyst . CEI did not operate effectively as a film catalyst under conditions of generation tried in this study . Generally , operation of the 2 - inch reactor with CEI catalyst was unsatisfactory because of poor reproducibility of the activation step and poor temperature control resulting in high- operating temperatures and eventual plugging of the reactor . Tests using CEI in fixed , packed beds suggest that the most likely application for CEI in producing high - Btu gas would be a moving - bed reactor , where sufficient bed movement and heat removal are provided to prevent plugging .

Jan 1, 1964

By R. J. Leary, W. M. Mahan, F. X. Tartaron

A new type of apparatus for prerefining molten blast furnace iron and to reduce the cost of subsequent steelmaking consists of a funnel - shaped device lined with firebrick into which a horizontal stream of molten pig iron is directed tangentially at the top . The rotary motion thus induced causes the stream to flatten itself upon the wall and flow in a spiral path to the outlet ; thus , the device was termed " vortex cone .' Oxygen and other refining agents are impinged upon the flowing metal in the cone where reaction is facilitated by the large metal surface exposed and the turbulent flow pattern . Experiments with water in 1 - foot - diameter funnels provided an idealization of the flow patterns to be expected with molten iron . A brick - lined reactor 3 feet in diameter was built for desiliconizing molten pig iron in lots of 1 to 2 tons . At flow rates of 0.3 to 0.5 ton min - 1 (430 to 720 tons per day ) this apparatus was 64- to 90 - pct effective in desiliconization with oxygen efficiencies of 19 to 41 pct . Detailed experiments to develop basic engineering data are underway , and adaptation of this principle to other reactions and reactants is planned .

Jan 1, 1964

By Charles J. Stehlik

This report deals with the changing behavior of mine roof bolt and roof rock as a result of repetitious production blasting . Observations were made in the upper shale production headings at the White Pine Copper Co. room and pillar mine , White Pine , Mich . Roof bolt compression pads and a stratascope were used in the investigations , which were carried out in three separate test sites in which nearly identical procedure produced comparative , repetitive , and anomalous observations . Results indicate roof bolt tension change and roof quality deterioration anomalies were coincident with blasting . The hypothesized cause of the anomalies is a seismic shock generated by the blasts .

Jan 1, 1964

By Sabri Ergun, Robert W. Smith, Victor H. Tiensuu

Factual geometries are considered for X- ray scattering studies of weakly absorbing materials by both reflection and transmission methods . These studies are usually made on slab specimens to obtain adequate scattered intensities ; however , the intensities are appreciably influenced by absorption of the X-rays in passing through the specimens . Conventional equations derived to account for this absorption are based on idealized geometries , but for polycrystalline carbons the use of idealized geometries leads to several percent error in the corrections to be made . Use of factual geometries substantially reduces this error .

Jan 1, 1964

By Robert K. Koch, Henry E. Blake

Laboratory tests were made to determine if aluminum fluoride of commercial grade could be synthesized by reacting alumina hydrate with dilute ( 25 to 75 grams per liter of fluorine ) aqueous fluoride solutions . • Products containing up to 90 percent aluminum fluoride ( A1F ) were synthesized by reaction of alumina trihydrate ( A120 3H2O) with either dilute hydrofluoric acid ( HF ) or ammonium fluoride ( NHF) solutions , the ammonium fluoride solution resulting from ammonia ( NH ) desilication of a hydrofluoricfluosilicic acid ( HF - H₂ SiF ) solution . Fluorine recoveries of over 80 percent were obtained with either type of solution . The hydrated precipitates of AlF, and ( NH4 ) , A1F ( ammonium aluminum fluoride ) obtained by reacting hydrated alumina with these solutions were subsequently converted to anhydrous AlF, by controlled heating .

Jan 1, 1964

By James S. Browning, W. H. Eddy

Laboratory batch and small - scale continuous flotation tests were conducted on a ferruginous barite - fluorspar ore from near Sweetwater , Tenn . , to determine the feasibility of producing commercial - grade fluorspar and barite concentrates . The lignin sulfonate - sodium fluoride - fatty acid method of floating fluorspar produced acid - grade concentrates . Flotation of the barite from the fluorspar tailing using petroleum sulfonate yielded concentrates suitable for use as a weighting agent in oil -well drilling muds . The continuous flotation tests , treating about 150 pounds of ore per hour , yielded fluorspar concentrates that assayed 98.3 percent CaF2 and barite concentrates that assayed 91.2 percent BaSO4 . The recovery of the two minerals was 91.2 and 85.2 percent , respectively .

Jan 1, 1964

By G. W. Birge, D. E. Wolfson, J. H. Lynch

Fourteen coal samples representing the Flag , Fire Clay , Whitesburg , Amburgy , Upper Elkhorn No. 3 , Upper Elkhorn No. 2 , Upper Elkhorn No. 1 , and Lower Elkhorn beds in Letcher County , Ky . , were carbonized by the Bureau of Mines - American Gas Association ( BM- AGA ) method , and yields of products and physical properties of cokes were determined . The samples tested were high- volatile A bituminous in rank , with dry , mineral - matter- free fixed - carbon contents ranging from 55.3 to 62.2 percent . Five of the samples , as received , were chemically unsuitable for metallurgical use because of excessive ash and/ or sulfur content . Generally , strength indexes of the cokes were low and all of the coals would require blending with higher rank coal to obtain satisfactory blast furnace fuel .

Jan 1, 1964

By Joe L. Castagno, Kenneth H. Johnston

Several hundred membrane - filter tests were made as part of a program to develop equipment and procedures to evaluate the quality of waters and to determine the quality of water suitable to efficiently flood oil sands of known permeability . Results indicated that neither the color of the water nor that of the precipitate on a membrane filter is a criterion for determining the quality of injection water . Reasons for poor water quality include poor operation of filtering systems , dirty filtering aggregates , excessive amounts of oil in injection water , commingling of incompatible waters , and excessive use of chemicals . A good water is required to efficiently flood sands of low permeability , but fair results may be obtained in flooding more permeable sands with poorer quality water .

Jan 1, 1964

By Henry M. Harris, Hal J. Kelly

Electrical dewatering tests are described in which the laboratory cells were designed for continuous operation using an endless metal belt as the anode . The test slurries were dilute , containing from 2.5 to 14.4 percent solids (specific gravity of 1.02 to 1.10 ) that were all minus 8 microns in size . Recovery of the solids of low water content was the practical objective of the investigation . Process variables evaluated and reported are : The effect of feed rate , amount of electrolyte , samples from different sources , and the use of two cells in series . These variables are evaluated on the basis of yield of clay per kilowatt - hour , recovery , and the amount of solids in the deposited clay . Recovery , yield , and solid content of the belt anode product are interdependent , and changes that will improve one of these characteristics often are accomplished at the expense of the others . Tests in which recoveries range from 50 to 60 percent usually result in yields of 8 to 9 kilograms (kg ) of dry clay per kilowatt- hour (kwhr ) . Under these conditions , the solid content of the deposited clay approximates 50 percent . One test sample , composed of kaolinite , showed very high yield , 13 to 16 kg per kwhr ; high recovery , 53 to 58 percent ; and 52 to 54 percent solids in the cake .

Jan 1, 1964

By F. E. Joyce, Charles Prasky

This report describes the response to high- temperature sulfatization of a variety of manganese minerals and companion compounds which may occur either as a principal component or as a gangue material in low- grade manganese deposits . Fourteen manganese samples representing oxide , carbonate , and silicate minerals as well as seven compounds which might occur as gangue with manganese minerals were tested batchwise in a bench- scale apparatus under conditions which would be favorable for the sulfatization of manganese . The manganese minerals substantiated thermodynamic predictions and responded to sulfatization but to varying degrees . The gangue materials , MgO , MgCO,, CaO , and CaCO3 , were sulfatized readily in contrast to the iron oxides and the aluminacontaining material which were not .

Jan 1, 1964

By I. L. Nichols, K. C. Dean, P. H. Johnson

Hydrochloric acid , sulfuric acid , and chloridizing roast- water leaching methods for dissolution of cesium and rubidium from Maine , Canada , and Southern Rhodesia pollucite ores and their flotation products were investigated by small- scale tests . Optimum conditions were determined to be ( 1 ) for hydrochloric acid leaching , use 12.7 equivalents of 8.8 normal acid per equivalent of cesium in the sample and leach for 6 hours at 100 ° C ; ( 2 ) for sulfuric acid leaching , use 12.7 equivalents of 14.4 normal acid and leach for 2 hours at 120° C ; and (3 ) for chloridizing roast - water leaching , roast minus 200 - mesh ore, limestone , and calcium chloride in a ratio of 2 : 4 : 1 , respectively , for 1 hour at 900 ° C , and leach the calcine for 1 hour at 80 ° C with enough water to give 35 pct solids . Extractions of cesium from ores and flotation products containing over 20 pct cesium were in excess of 97 , 93 , and 96 pct for the hydrochloric acid , sulfuric acid , and chloridizing roast - water leach processes , respectively .

Jan 1, 1964

By F. W. Hoertel

Tungsten from the hydrogen reduction of WF was vapor - deposited to coat MERM (Material Evaluation Rocket Motor ) graphite and rhenium- lined graphite nozzles . These nozzles have surface configurations that preclude the conventional fabrication of high- density- tungsten liners . Operation at 550 ° C produced selectively placed uniform coatings of specified thicknesses at near theoretical density . An acceptable coating could not be deposited on a beryllia nozzle because of an undesirable side reaction between the substrate and one or more of the products of the reduction reaction .

Jan 1, 1964

By Wilbur I. Duvall

This paper presents arguments which show that a velocity seismograph should be used to measure building and ground vibrations produced by blasting . However , portable velocity seismographs suitable for this type of measurement are not commercially available . The paper describes how a velocity seismograph can be assembled from commercially available velocity gages , amplifiers , and recorders . Also , specifications are given which could be used in the design and manufacture of a portable velocity seismograph suitable for measuring vibrations from blasting .

Jan 1, 1964

By H. A. Dierks, H. B. Link

The purpose of this investigation was to develop a practical feeder apparatus to introduce comparatively large pieces of coal and similar material into a pipeline under pressure in connection with the vertical hydraulic transportation of solids , termed " hydraulic hoisting . " This method of hoisting the precrushed run - of - mine product of an underground mine has been given unusually wide attention abroad and could be of considerable significance to the U.S. mining industry in its search for operating improvements and cost reduction . A lock-hopper assembly was developed after a series of sinking velocity tests were made by dropping anthracite in a column of water . The system functioned reliably as an automatically operated feeder apparatus .

Jan 1, 1964

By Robert H. Merrill, James V. Williamson, David M. Ropchan, George H. Kruse

In- situ rock stresses were determined by flatjack and borehole - deformation methods . Estimates of the stress distribution around a flatjack were obtained by a combination of flatjack and borehole - gage techniques . The investigations were part of a study , conducted jointly by the State of California and the Federal Bureau of Mines , to determine the stress in rock at the site of an underground powerplant for the Oroville Dam near Oroville , California . The stress distribution around each of three flatjacks was nonsymmetric ; however , stresses obtained from 9 flatjack and 157 borehole measurements are considered reasonably accurate for engineering purposes . The stress near the edge of the openings is between 800 and 1,600 psi ; the stress in the undisturbed rock is approximately 500 psi , nearly hydrostatic .

Jan 1, 1964

By F. E. Block, Stephen D. Hill

The necessity for measuring radiation dose is encountered in studying both the beneficial and damaging effects of ionizing radiation on materials . It is also necessary to know the radiation dose absorbed by the reactants in order to evaluate the efficiency of reactions or processes that are promoted by radiation . Thus , a significant effort was made at the Albany cobalt 60 facility to investigate techniques by which the exposure radiation dose can be determined . Methods including ferrous sulfate , ceric sulfate , and methyl methacrylate chemical dosimeters , ion chamber dosimetry , and an absolute radiation calorimeter were investigated . Isodose curves were constructed for several standard source configurations using the dosimetry techniques which were investigated .

Jan 1, 1964

By K. D. Plants, J. H. Holden, L. F. Willmott

Pulverized high- volatile A bituminous coal was gasified with oxygen and superheated steam in a pressure - gasification pilot plant equipped for steampickup feeding . The pilot plant operated satisfactorily at relatively high steam- to - coal ratios , but steam- to - coal ratios could not be reduced much below 0.5 lb / lb without condensation of steam or softening of the coal . Carbon gasified , gas composition , and coal and oxygen requirements were essentially the same as for a pilot plant equipped with a fluidized coal feeder . Average results from the pilot plant equipped for steam- pickup feeding were coal requirement , 37.3 lb/M ( 1,000 ) scf of CO + H₂ produced ; oxygen requirement , 358 scf /M scf CO + H₂ produced ; and carbon gasified , 87.7 percent .

Jan 1, 1964

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

Electrolytic studies were conducted to determine the transfer rates of the alloying constituents from molten titanium anodes to solid titanium cathodes in molten salt systems . The metals , nickel , tin , copper , bismuth , and manganese , were selected on the basis of thermodynamic data and the melting point of the alloy system . The transfer of nickel , tin , and bismuth was very low . The content of these elements in the cathode was in the range of less than 0.01 to 0.001 percent . The copper transfer was 0.6 to 0.8 weight - percent in electrolytes containing titanium chlorides and 0.12 weight - percent in titanium fluoride salt systems . The manganese transferred at rates comparable to that of titanium . Highpurity titanium and titanium- manganese alloys of uniform composition were produced by electrorefining molten titanium alloys in chloride electrolytes . Comparisons are made between the calculated and the actual quantities of metal transfer .

Jan 1, 1964