摘要:

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

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1945.tb14496.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

摘要:

AbstractA set of factors is derived for calculating the glass density changes caused by moderate changes in composition. These are similar to those of Ghering and Knight but indicate that portion of the total density change due to each oxide. They also give directly the approximate density change caused by dilution.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1945.tb14497.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

摘要:

AbstractA procedure is outlined for deriving the relationship betweennDandvfor binary glass systems, using constants previously published by Huggins and Sun.1As an example, the Na2O‐SiO2system is discussed and the results are plotted in two ways. An equation is deduced for the slope of thenDversusvcurve at any composition, and initial values of this slope, at the SiO2end, are tabulated for various MmOn‐SiO2syst

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1945.tb14498.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

摘要:

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.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1945.tb14499.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

摘要:

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‐alum

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1945.tb14500.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

摘要:

AbstractNickel flashing as applied to enameling stock is shown to be primarily metallic nickel. The role of nickel in developing enamel adherence is apparently bound up with the retardation of oxidation which the nickel flash imparts in the enameling cycle. The problem of adherence may be considered to be a corrosion phenomenon of the base iron developed by the action of gases and other agents which may be present at enameling temperatures. As such, the degree of adherence is a function of oxygen pressure at the interface when the glass is fused. The equilibria developed are strongly affected by the presence of nickel.Using cover coats directly on iron, the amount of nickel required will vary with each particular enamel composition. Şome evidence as to the nature of the adherence‐promoting oxide is present

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1945.tb14501.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY

摘要:

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 measu

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1945.tb14502.x

出版商:Blackwell Publishing Ltd    

年代:1945

数据来源: WILEY