摘要:

AbstractEighteen samples of wall tile and 15 samples of tableware, which had been in service or in storage for periods of time ranging from 23 years to less than 1 year, were tested to determine how much moisture expansion had taken placc. Selected samples were also autoclaved, and the resultant moisture expansions were compared.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1941.tb14824.x

出版商:Blackwell Publishing Ltd    

年代:1941

数据来源: WILEY

摘要:

AbstractA general investigation was made of the thermal expansion of various silicate fluxes The fluxes considered in the crystalline (anisotropic) and glassy (isotropic) states. were ten feldspars, two nepheline syenites, anorthosite, aplite, and lepidolite.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1941.tb14825.x

出版商:Blackwell Publishing Ltd    

年代:1941

数据来源: WILEY

摘要:

AbstractSpecimens of fine‐grained, red‐firing clay, which had been fired to temperatures corresponding to various stages of vitrification, were subjected to 200 cycles each of wetting at 100°F. and drying at 100°F. and 60% of relative humidity. This treatment, simulating weathering in mild climates, caused (1) a permanent gain in weight which was greater for the softer specimens; (2) a moisture expansion for the softer specimens but none for those near vitrification; (3) a fairly uniform decrease in modulus of elasticity for all specimens; and (4) a decrease in modulus of rupture for the softer specimens but an increase in strength for those that were completely vitrified. The data indicate that moisture expansion and a decrease in strength of soft‐fired clay bodies, caused by repeated wetting and drying, may be eliminated by proper vitrif

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1941.tb14826.x

出版商:Blackwell Publishing Ltd    

年代:1941

数据来源: WILEY

摘要:

AbstractTests on the deposit of massive topaz in Chesterfield County, South Carolina, show that the mineral has a P.C.E. of 40 and a low permanent expansion. Most of the fluorine and water are driven off between 850° and 900 ° C. The fluorine, however, carries off with it some of the iron and considerable silica. The physical properties of a fire‐clay refractory in which different amounts of topaz are used to replace flint fire clay have also been investiga

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1941.tb14827.x

出版商:Blackwell Publishing Ltd    

年代:1941

数据来源: WILEY

摘要:

AbstractA study was made to determine the factors that should be considered to get maximum reflectance with a given enamel. The increased reflectance obtained by fine grinding varies according to the kind of frit and opacifier used, and it was found that the proper combination of frit and opacifier is essential in developing effective reflectance. The writers conclude that the efficiency of the opacifiers varies according to the amount used; the method of blending the frits is an important factor; and the kind of clay used in the mill addition affects the degree of reflectance.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1941.tb14828.x

出版商:Blackwell Publishing Ltd    

年代:1941

数据来源: WILEY

摘要:

AbstractReflectometers are widely used to give a numerical rating for the comparative whiteness of porcelain enamels, but these instruments occasionally show values in disagreement with a careful visual comparison. To find the reason for this disagreement, a survey was made to determine the effect of residual color on the consumer rating of porcelain enamel whites. A series of 12 white plaques was made ranging from 67 to 75% in reflectance, from 478 to 485 m/x in dominant wave length, and from 1.6 to 5.6% in residual color. These specifications were determined from curves run on a Hardy G. E. recording spectrophotometer. The 12 plaques were submitted to 36 persons who arranged them in order of whiteness. The order of arrangement was compared statistically, and the whites were rated in their order of acceptance. Residual color was found to have an important effect on apparent whiteness, and of these typical porcelain enamel whites, those most highly colored (blue) were preferred.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1941.tb14829.x

出版商:Blackwell Publishing Ltd    

年代:1941

数据来源: WILEY

摘要:

AbstractX‐ray diffraction studies have been made of two samples of potash‐silica glass whose composition is 20.9% and 29.1% of K2O by weight. A Fourier analysis of the intensity curves indicates a structure similar to that found in soda‐silica glass. Each silicon is tetrahedrally bonded to 4 oxygen ions, with each oxygen bonded either to 1 or 2 silicons. The K+potassium ions are situated in holes in the silicon‐oxygen network with an average of about 10 oxygen ne

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1941.tb14830.x

出版商:Blackwell Publishing Ltd    

年代:1941

数据来源: WILEY

摘要:

AbstractQuantitative data are presented, and conclusions are drawn regarding the molecular nature of elastic and viscous processes in certain silicate glasses.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1941.tb14831.x

出版商:Blackwell Publishing Ltd    

年代:1941

数据来源: WILEY