bluuebunny/crossref_metadata_2025_split huggingface dataset:
NOTES ON MOISTURE EXPANSION*
Authors: Thiemecke H. 
Published: June 2006

AbstractMoisture‐expansion determinations were made over a period of more than three years on bisque and glazed specimens of two types of semivitreous bodies having approximately the same absorption which were exposed to four different atmospheric conditions. The data indicate the cone 0 tale‐pyrophyllite body to expand less under all conditions of exposure than the cone 9 clay‐flint‐feldspar body. Glazed specimens of both bodies expanded more than the bisque specimens and a possible explanation is given. From mathematical considerations, a three‐year storage period appears to be sufficient to permit moisture expansion that closely approaches the ultimate which might be expected in the types of bodies investigated. The autoclave treatment gave the highest expansion values and should serve as an index of the service performance as to delayed crazing of ware so tested.
DIFFERENTIAL THERMAL ANALYSIS OF CLAYS AND SHALES, A CONTROL AND PROSPECTING METHOD*
Authors: Grim R. E. , Rowland R. A. 
Published: June 2006

AbstractThe differential thermal method, by determining the thermal reactions undergone by a clay or shale, is a rapid means of identifying the mineral components of such materials, and because the properties of clays and shales depend largely on their mineral composition, it is at the same time a rapid method of evaluating the properties of such materials.Differential thermal analyses are presented for the pure forms and synthetic mixtures of the common components of clays and shales, namely, kaolinite, halloysite, illite, montmorillonite, quartz, gibbsite, boehmite, diaspore, dolomite, calcite, gypsum, organic material, pyrite, marcasite, goethite, and limonite.Differential thermal analyses are presented also for a variety of well‐known types of clays, and on the basis of the thermal data for the pure components, the mineral composition is indicated. The correlation of mineral composition of clays and shales (as reflected in the differential thermal curves) with the ceramic properties is discussed as a basis for using this thermal method to indicate the properties of such materials.Finally, differential thermal analyses are presented for sequences of samples from the pits of several operating clay products plants in order to illustrate the way in which the method can be applied in prospecting and in plant control.
DEVITRIFICATION CHARACTERISTICS OF ALKALI‐LEAD OXIDE‐DOLOMITE LIME‐SILICA GLASSES*
Authors: White J. F. , Silverman W. B. 
Published: June 2006

AbstractThe devitrification characteristics of the field of compositions, which includes the commercial lime crystal glasses, were investigated. Tridymite was found to crystallize from glasses containing as low as 62% of SiO2. Tridymite, devitrite, diopside, sodium disilicate, and an unidentified compound were found to be primary phases. Potassium oxide (K2O), in general, lowers the liquidus temperature when it replaces Na2O.
OPTICAL FLUOR‐CROWN GLASSES*
Authors: Fraser Walter A. , Upton Lee O. 
Published: June 2006

AbstractThe effect of variations in composition on optical properties was studied. The index of refraction is lowered by the substitution of fluorine and alumina for silica; the reciprocal dispersion, however, is increased by fluorine and lowered by alumina so that fluorine and alumina can be balanced against each other to give almost any desired optical properties within the field investigated, that is, in the range of 1.46 to 1.50 for index of refraction and 63 to 70 for the reciprocal dispersion.
VISCOSITY OF RECENT CONTAINER GLASS*
Authors: Robinson Howard A. , Peterson Charles A. 
Published: June 2006

AbstractA high‐temperature, concentric cylinder viscometer has been constructed and calibrated. The calibration checks within 1% that obtained by Lillie for a similar apparatus and provides further evidence of the high degree of reliability of this type of measurement. The contention of Washburn and Shelton that the calibration in such instruments is a function of the viscosity is shown to be false. Because four independent investigations have been unable to check this contention, it may now be regarded as spurious. A medium temperature‐range fiber viscometer for measuring the viscosity of glass in the annealing range has also been constructed. It is shown that the Fulcher equation, log η=−A+B/T−T0, fits the data obtained on the two instruments to within 0.5% for commercial soda‐lime glasses. Complete viscosity data as a function of temperature are given for sixteen commercial container glasses, and the analyses are also included. These glasses show a wide range of viscosity.
ANALYSIS OF CORDS AND STONES*
Authors: Zarbo G. J. , Hunt H. J. , Smith D. C. 
Published: June 2006

AbstractA method is described for the separation of cords and stones from the surrounding glass, and procedures are given for the semimicro‐determination of silica and alumina. The apparatus is illustrated. Analytical results by full‐scale methods and semimicro‐methods are given. The methods of semimicro‐analysis are shown to be rapid and accurate.
SURFACE TENSION AND PERSISTENCE OF CORDS IN GLASS*
Authors: Knight Mellen A. 
Published: June 2006

AbstractThe action of surface tension in molten glasses is discussed in relation to cord persistence. An examination is made of the reported mechanism for the solution of cords as proposed by Jebsen‐Marwedel. His viewpoint that the shape of immersed cords is governed by surface‐tension differences between the cord and matrix glasses appears to be in conflict with the physics involved. The possible influences of inter‐facial tension on the shape of cords and on their location in or on the melt are considered along with its relation to other physical forces. It is concluded that the only stable form for cords under the influence of interfacial tensions alone is a spherical one. Other factors, such as high viscosities, varying diffusion rates, and mechanical and thermal stirring cause the irregular shapes found in practice. The relation of surface tensions to these factors requires further study.
SURFACE LAYER OF SHEET GLASS*
Authors: Bishop F. L. 
Published: June 2006

AbstractThis research was conducted to obtain evidence of the nature of the fire polish on sheet glass. Three measurements were made on each sample as follows: (1) The deviations from Fresnel's reflection laws, (2) a measurement based on the Pfund method of determining the apparent Brewsterian angle as compared to that calculated from the index of refraction of the glass, and (3) the true index of refraction by a prism method in which the samples were cut and ground to 60‐degree prisms. These measurements showed that freshly drawn sheet glass probably has a crystalline layer several molecules thick on the surface. The layer has a high index of refraction, but this is counteracted quickly by water absorption if the glass is dampened slightly or is exposed to the atmosphere.
CALCULATION OF SURFACE TENSIONS OF GLASSES*
Authors: Lyon K. C. 
Published: June 2006

AbstractFactors have been derived for the calculation of the surface tensions of glasses from their compositions at temperatures of 1200° and 1400°C. The nine oxides evaluated are those commonly found in significant amounts in glass compositions. The surface tension of a glass may be calculated with a fair degree of assurance from its composition to within about 4 dynes per cm.
OPTICAL GLASS FROM THE VIEWPOINT OF THE LENS DESIGNER*
Authors: Kingslake R. 
Published: June 2006

AbstractThe glass used in the manufacture of lenses must be chemically stable and substantially free from bubbles, color, and striae. The lens designer is then concerned only with the refractive index and the dispersive power of the available glasses. Because practically every new lens must be achromatic, the positive elements used in it must be made from glass having a low dispersive power; the negative elements must have a relatively high dispersive power. The choice of refractive index is determined by many conflicting factors because the only “tools” available to the designer for the correction of many different aberrations are the radii of curvature of the lens surfaces, the thicknesses and air spaces, and the refractive indices of the glasses. The range of optical glasses commercially available and the reasons underlying the designer's selection of glass for different kinds of lenses are discussed.
II, CORRELATION OF GLAZE THICKNESS WITH AIR PERMEABILITY*
Authors: Harman C. G. , Blanchard M. K. 
Published: June 2006

AbstractAn attempt was made to correlate the thickness of deposition of glazes with the air permeabilities of the bodies. The correlation was satisfactory under certain restricted conditions but not for general cases. An adequate correlation was obtained, independent of the type of body, between thickness of glaze deposition, glaze consistency (coherence value), and water receptivity.
SOME FACTORS AFFECTING THE P.C.E. OF SILICA FIRE CLAY*
Authors: Birch Raymond E. , Hall Morris P. 
Published: June 2006

AbstractA study was made of the factors affecting the pyrometric cone equivalent (P.C.E.) of silica fire clay made of ganister, clay, and silica‐brick culls. These factors include grind, mix proportions, and quality of raw materials.
HIGH‐ALUMINA CLAYS OF PULASKI AND SALINE COUNTIES, ARKANSAS*
Authors: Tracey Joshua I. 
Published: June 2006

AbstractExtensive deposits of kaolinitic clay and closely associated bauxite occur in Pulaski and Saline counties, Arkansas, as products of early Cenozoic weathering of nepheline syenite. The clays of the bauxite‐kaolin deposits normally contain more than 35% of alumina. Siderite is the principal impurity. The deposits for the most part are buried beneath sediments of Wilcox age or younger, but the overburden is thin or absent near outcrops of syenite. Deposits beneath overburden that does not exceed 50 feet in thickness probably total more than 100 million tons.
PROPERTIES OF ENAMEL SLIPS: I, GENERAL PROPERTIES OF CLAYS AND ENAMEL SLIPS*
Authors: King Burnham W. , Carter Herbert D. , Draker Harry C. 
Published: June 2006

AbstractFive clays used to suspend porcelain enamels and their properties were studied. Fundamental data were first obtained on the clays, which were then milled in different proportions with several types of porcelain enamel frits. The properties of the resulting slips were studied. The pickup weight, that is, the amount of enamel retained on a ground‐coated plaque which had been dipped in the slip and allowed to drain, was used as a basis of comparison.
SUBSTITUTION OF TOPAZ, DOMESTIC KYANITE, AND SYNTHETIC MULLITE‐CORUNDUM FOR INDIA KYANITE: IV, RAW TOPAZ AS HIGH‐TEMPERATURE BOND FOR DOMESTIC KYANITE*
Authors: McVay T. N. , Galbreath W. W. , Allen Dan 
Published: June 2006

AbstractRaw topaz has been found to act as a high‐temperature bond for both raw and calcined kyanite. It is thought that this bonding action is due in part to volatiles which emerge from the raw topaz between 1000° and 1200°C. Some of the topaz decomposition products are absorbed and retained by the calcined kyanite. Within the limits of this investigation, all refractories which contained either calcined or raw kyanite, or mixtures of the two, with a minimum of 10% raw topaz had a good structure and were well bonded. The results of the load tests indicated that increased firing temperatures in the preheat improved the load resistance, but excellent high‐temperature resistance was obtained by preheating as low as 1300°C. in laboratory kilns.
VARIATIONS OF REFRACTIVE INDEX OF GLASS WITH TIME AND TEMPERATURE IN ANNEALING REGION*
Authors: McMaster Harold A. 
Published: June 2006

AbstractThe refractive index of a rapidly cooled fiber of borosilicate glass was found to increase according to the equation, 1/(N6–N) – 1/(N6–N0) =At, where t is time, N6 is equilibrium index, and A is a constant at constant temperature. Index data were plotted according to this equation to determine, graphically, values of N6 and A for several temperatures between 914° and 1060°F. Values of N6 for temperatures from 1060° to 1180°F. were determined by prolonged heating of the glass at each 20° interval. The change of A with temperature was found to be well represented by the equation, log A=K/T+C, where T is the absolute temperature and K and C are constants.
SOFTENING POINT OF GLASS BY FIBER ELONGATION METHOD AND IMPROVEMENTS IN APPARATUS AND PROCEDURE*
Authors: Falter Arthur H. 
Published: June 2006

AbstractDetail and assembly illustrations show how the apparatus has been redesigned to maintain a constant rate of heat transmission. A description of the comparator telescope and the method of use is given. Individual curves show the results of softening‐point tests on glasses over a range of 260°C., in which the agreement for five individual homogeneous glass specimens varies from 1° to 6°C. when the ordinary portable potentiometer is used. When the glass contains stones or is devitrified, the results are more widely divergent. Uniformity of specimen diameter has a slight effect on the results.
LEWIS ACID‐BASE THEORY APPLIED TO GLASS*
Authors: Sun Kuan‐Han , Silverman Alexander 
Published: June 2006

AbstractAccording to the Lewis theory of acids and bases, glass formers, such as SiO2, B2O3, P2O5, BeF2, GeS2, etc., may be classified as acids because they are electron‐pair acceptors in glass reactions and the modifiers, Na2O, CaO, NaF, Na2S, etc., are bases because they are electron‐pair donors; Al2O3, Fe2O3, BeO, MgO, ZnO, etc., the intermediates, may be classified as amphoteric.
SOME PROPERTIES OF SODA‐SILICA GLASSES AT HIGH TEMPERATURES*
Authors: Sun Kuan‐Han , Safford Hurd W. 
Published: June 2006

AbstractA study is made of density, expansion, surface tension, parachor, and viscosity data for glasses in the system Na2O‐SiO2 within the temperature range 900° to 1400°C. The best values have been selected and correlated with composition.
EFFECT OF MIGRATION OF CLAY MINERALS AND HYDROUS ALUMINUM OXIDES ON THE COMPLEXITY OF CLAY*
Authors: Allen Victor T. 
Published: June 2006

AbstractMovement of montmorillonite, nontronite, kaolinite, halloysite, dickite, gibbsite, and diaspore within clays after they were first formed is indicated by the relations reported in this paper. Migration of these minerals takes place rarely by transfer of their constituents as true solutions but generally as colloidal suspensions whose formation and movement are favored by conditions of good drainage and the presence of dispersing agents. This migration increases the complexity of the clays affected by it and accounts for some of the variations in the composition of a single body of clay met by the clay producer.
CRAZING OF ENAMEL ON STOVE TOPS DUE TO HEATING IN SERVICE*
Authors: Fellows Roger L. 
Published: June 2006

AbstractExamination of stove tops that had crazed in service show two types of crazing. One is in the form of a network of cracks which may be attributed to thermal shock, while the other is in the form of parallel lines and occurs in the normal use of the stove without any particular abuse. In studying the latter type of failure, localized heating of the stove top causes a cross‐bend failure of the enamel due to flexing from the heat, and the higher the temperature the less is the amount of deflection required to cause failure. The temperature necessary for this condition is lower than 550°F. Sample plates subjected to various tests afforded a means of studying the different variables that produce crazing in stove tops.From these tests, the following observations are made: (1) Stove tops that have tensile strains in the enamel due to fabrication or assembly are likely to craze in the areas of these stresses if they are heated; (2) the lower the coefficient of expansion of the cover‐coat enamel, the less likely is the enamel to craze; (3) the lighter the weight of application of cover coat, the greater is the resistance to crazing; (4) the heavier the gauge of metal the greater is the resistance to crazing; and (5) heating the enamel over a long period of time tends to induce crazing.
ANNEALING STRAINS IN GLASS AND THEIR DEGREE OF PERMANENCE*
Authors: Ghering L. G. , Green T. D. 
Published: June 2006

AbstractA statistical comparison has been made of 13 sets of measurements of optical path difference, taken over a seven‐year period, on 24 samples of the standardized disks distributed in 1938 to the manufacturers of glass containers. These data show that the original optical retardation of about 22.8 millimicrons has not changed by more than =1.3%, equivalent to =0.30 millimicron or =0.10° on the scale of the measuring instrument.Five tests were made in 1938, five in 1945, and three between. The standard deviation of the combined errors for each of the 13 averages of 24 measurements is =0.0338° and is composed of an accidental error of observation of =0.005° and an error of adjustment of the instrument of =0.0333°. The range of =1.3%, or =0.10°, beyond which the disks could not have changed over seven years, represents the 3‐sigma probability limit of combined errors.While this possible change of =1.3% would be insignificant in relation to the utility of the standardized disks, it represents a possible experimental error too great to permit broad conclusions concerning the ultimate stability of birefringence in strained glass.
GLASS DENSITIES BY SETTLING METHOD*
Authors: Knight Mellen A. 
Published: June 2006

AbstractA simplified sink‐float apparatus and method for measuring the densities of lumps of glass are described. Several lumps, of approximately two grams weight, of unknown density and one lump of glass of known density are placed in a heavy‐liquids mixture contained in a test tube. The tube is immersed in a water bath that is heated automatically at a uniform rate; as the lumps settle, the temperature is noted at which each lump passes a reference line marked on the tube. The density of each unknown may be expressed simply in terms of the difference between its temperature and that for the standard lump, or these temperature differences can be converted to density differences or to absolute densities. The precision (reproducibility) of the measurements is represented by a standard deviation of approximately =0.0001 gm. per cc.The method is rapid and convenient and requires a minimum of training of the operator. It is believed to be more practical for plant laboratories than the other available methods. It is especially applicable to measurement of daily densities for production control in glass plants and to trouble‐shooting investigations of composition heterogeneities; large numbers of samples can be tested rapidly and precisely. Complete information as to sampling, operation, and calculations is given.
TRACING FLOW IN GLASS TANK FURNACES*
Authors: Bishop F. L. 
Published: June 2006

AbstractBy adding a small amount of a rare earth to a definite portion of batch, the velocity, direction, and amount of surface flow can be determined. The flow measurements are calculated from the resultant slight fluorescence of samples taken at intervals or by the change in transmission for certain wave lengths of ultraviolet light. Sample results are shown and discussed.
VISCOSITY STUDIES OF SYSTEM CaO–MgO–Al2O3–SiO2:1, 40% SiO2*
Authors: Machin J. S. , Hanna D. L. 
Published: June 2006

AbstractThe measurement of glass viscosities at elevated temperatures with an oscillating cylinder‐type viscometer is described. Viscosity data are presented covering those compositions in the CaO–MgO–Al2O3–SiO2system which contain 40% SiO2and which are liquid at 1500°C. The pattern of the system of isokoms presented indicates that viscosity is closely related to the ratio of basic to acidic components. Theoretical aspects of the variation of viscosity with composition in silicate‐aluminate systems are discussed in terms of silica‐alumina polymers.
DETERMINATION OF REFLECTANCE OF WHITE ENAMEL FRITS BY TURBIDITY METHOD*
Authors: King R. M. 
Published: June 2006

AbstractA method for the determination of the reflectance of powdered frits is described. Results obtained by this method show a high correlation with the results of standard reflectance tests, particularly when frits are fused at enameling temperatures.The method consists essentially of suspending 0.4 cc. of sample, sized between 270‐ and 325‐mesh, in 10 cc. of clear kerosene and measuring by means of a photoelectric cell the decrease in light transmitted as compared with the light transmitted by kerosene itself. The Cenco‐Sheard‐Sanford photelometer was used for these measurements.
COATINGS FOR WIRE‐WOUND RESISTORS*
Authors: Marbaker Edward E. 
Published: June 2006

AbstractThis paper describes the experimental work carried out by the O. Hommel Fellowship, Mellon Institute, under a contract made by the O. Hommel Company with the War Production Board, to develop a coating for wire‐wound resistors which would pass the Grade 1, Class I qualification tests of Army and Navy Specification JAN–R–26. An outline of the methods used, a general survey of the types of coating considered, generalizations concerning requirements, and conclusions are presented.The work included studies of the conventional enameled Nichrome‐wound, steatite tube resistors which consisted of an investigation of the properties of tubes made from steatite and other ceramic bodies and the testing of vitreous enamels formulated for use as resistor coatings.When it became apparent that steatite tubes are not perfectly resistant to thermal shock and that the disparity among the expansivities of the component elements of this type of resistor is so great that the formulation of an enamel having satisfactory properties is very difficult, if not impossible, an extended effort was made to develop a resistor in which the wire was wound on a pre‐enameled steel core and then coated with a suitable cover‐coat enamel. Considerable progress was made on the enamel‐coating studies, but non‐short‐circuiting terminals were found to be necessary and a completely satisfactory design was not worked out except for testing purposes.A resistor that fulfilled the requirements of resistance to thermal shock and moisture penetration was developed from a tube of zircon porcelain, wound with Kovar wire and coated with Pyrex‐brand glass, the expansivities of all of which are low and within a relatively narrow range. Except for the fact that the wire used in this combination has too high a thermal coefficient of resistance, this type of resistor is capable of meeting the Grade 1, Class I specification.A recently developed silicone paste was applied to various types of tubes wound with a standard resistance wire fastened to copper tabs or to ferrules and cured at a maximum temperature of 375°C. This coating has a rubbery consistency and is not wet by water. Resistors coated with this material have fulfilled the requirements of Grade 1, Class I qualification tests.
LABORATORY CORROSION TESTS OF ROTARY LIMEKILN REFRACTORIES*
Authors: Pole Gordon R. , Beinlich Alfred W. 
Published: June 2006

AbstractA modification of the Hugill, Ainsworth, and Green laboratory method for determining the corrosive action of lime on refractories was used to indicate the best refractory for rotary limekilns. An intermediate handmade refractory, two high alumina, two superduty, and two first‐quality, stiff‐mud refractories were tested. It was found that the depth of penetration of the lime attack decreases with an increase in alumina content of the refractory. Better resistance of the 70% aluminous refractories to slagging was indicated by the small‐scale tests which were substantiated by plant‐scale operation.
FACTORS INFLUENCING FLUXING ACTION OF VARIOUS OXIDES IN LOW‐TEMPERATURE BOROSILICATE GLASSES*
Authors: Swift Howard R. 
Published: June 2006

AbstractStrontium, barium, and lead oxides were studied as fluxes in low‐temperature borosilicate glasses by using the button‐flow method. It was found that strontia may be superior to lead oxide as a flux in glasses high in fluorides and low in alumina. This result was explained by the greater solubility of fluorides in strontia glasses, in which case the two fluxes, strontia and fluorspar, are acting together.