ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1955.tb14934.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY

摘要:

The concept of glass as a polymer of silicon, phosphorus, or other glassforming atoms connected by oxygen atoms suggests that fibers with oriented linear chains may be prepared. Previous attempts to demonstrate such orientation have failed, however, with glasses of the usual compositions. The composition in which linear chains seem most likely to occur is that of the “meta” salts in which each glassformer is bound, on the average, to two others through oxygen atoms. Under drawing conditions indicated by the theory of viscoelastic properties of high polymers, fibers of sodium metaphosphate glass have been prepared that show birefringence and give X‐ray diffraction patterns similar to those of organic fibers with oriented chain molecules. Under analogous treatment sodium metasilicate failed to give such ef

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1955.tb14935.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY

摘要:

A series of porcelain enamel ground coats of the same basic composition but with various amounts of cobalt oxide was fired on enameling iron in atmospheres consisting of various oxygen‐nitrogen mixtures. The effect of the oxygen content of the atmosphere on adherence was determined and the effect on interface roughness was estimated from an examination of metallographic cross sections. A decrease in the amount of oxygen in the firing atmosphere necessitated an increase in the amount of cobalt oxide in the enamel if optimum adherence was to be secured. Ground coats containing 3.2% cobalt oxide or more developed a weak but definite bond in oxygen concentrations as low as 0.02 mole %. A qualitative correlation was found between adherence and surface roughness regardless of the oxygen content of the firing atmospher

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1955.tb14936.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY

摘要:

Samples of nepheline syenite prepared by conventional and by fluid‐energy reduction methods were studied to determine (1) their fundamental properties and (2) the characteristics they impart to vitreous bodies. Fluid‐energy grinding methods make it possible to obtain materials which pass a 325‐mesh sieve and yet do not have excessive amounts of extreme fines. The absence of large flux particles is conducive to a uniform distribution of the resultant glassy phase which permits a closer approach to equilibrium conditions and improves the physical properties of whiteware b

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1955.tb14937.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY

摘要:

Various methods of preparing the technically important ferrospinels are discussed; particular attention is given to the reactivity and homogeneity of the final mixture. The reactivity and intimacy of mixing of the initial components may be improved by the use of chemical methods of comminution and mixing, viz., thermal decomposition of the mixed chemicals, chemical precipitation of the components, or ignition of the components in a fine state of division. The use of controlled partial pressures of oxygen (CO2‐CO mixtures) for the preparation of magnetite and manganese ferrite is discussed. The feasibility of the application of these methods on a commercial scale is outline

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1955.tb14938.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY

摘要:

High‐purity calcite of 10/20 mesh was calcined at various heating rates and fired to various maximum temperatures to determine the effect of these variables on the densification of the CaO produced. It was found that the heating rate during dissociation had a great bearing on densification. Shock heating conditions at temperatures between 2200° and 2530°F. gave bulk density values which were abnormally

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1955.tb14939.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY

摘要:

Theoretical relationships and experimental data concerning thermal conductivity for a number of oxide materials have been compared over a wide temperature range. Deviations from the basic proportionality betweenkand 1/Tare caused by radiant‐energy transmission, a high Debye temperature, a low mean free path of the thermoelastic waves, porosity, and in a few cases electronic conductivity. Extrapolation of thermal conductivity data to high temperatures is not reliabl

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1955.tb14940.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1955.tb14941.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY