摘要:

AbstractPetrology is concerned with the rocks and mineral deposits of the earth's crust. Like all natural sciences, it developed through a descriptive stage in which the principal emphasis was placed on the collection and correlation of facts. Interpretation recently has been increasingly stressed, and it has been realized that to reach reliable conclusions regarding the origin of earth materials experiment is an indispensable aid.The petrologist, acting on this conviction, has studied the behavior of various earth materials subjected in the laboratory to a wide range of temperatures, pressures, and chemical environment. He has thus been enabled to reach certain conclusions regarding the conditions to which these materials wfere subjected during the natural processes by which they were formed. Inevitably he discovered a great many facts of service to the mineral technologist.Some of the industrial processes developed by the mineral technologist have in return served to supplement the laboratory experiments of the petrologist. Some aspects of this mutual service of mineral technology and petrology are discussed.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1943.tb15216.x

出版商:Blackwell Publishing Ltd    

年代:1943

数据来源: WILEY

摘要:

AbstractThe solid solution of P2O5in calcium orthosilicate, 2CaO†SiO2, was studied by means of thermal and optical methods, and the inversion temperature for the alpha to beta 2CaO.SiO2change was found to be lowered by the presence of the dissolved P2O5.With this information concerning the solid solution of PaO5in the high‐temperature forms of 2CaO.SiO2, a probable mechanism is presented for the inhibiting effect of P2O5and similar oxides on the beta‐gamma inversion (dusting) of 2CaO . SiO2. Two new crystal chemically inhibiting oxides (As2O5, V2O5) are listed.The types of inhibition of the beta‐gamma inversion are distinguished as (1) physical, wherein the constraint imposed by the surroundings acts to prevent the inversion, isolate the grains of 2CaO . SiO2, and interrupt the continuity of the inversion wave, and (2) crystal chemical, wherein the presence of foreign dissolved substances apparently produces a true stability in the beta lattice at room temperature. The mechanism of the crystal‐chemical inhibition is discussed in some detail. The information is applied to the problem of stabilizing 2CaO . SiO2in dolomite or lime‐s

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1943.tb15217.x

出版商:Blackwell Publishing Ltd    

年代:1943

数据来源: WILEY

摘要:

AbstractIn cooperation with the Modular Service Association, studies have been made during the past two years on present unit masonry sizes as used in conventional building construction and their adaptability to a coordinated system. It was found that a significant relationship exists between present unit sizes in height, thickness, and length and a 4‐in. modular dimension. There is little consistency, however, in the assembly of these units in similar or composite walls and far less in the coordination with component building materials and equipment.Recommendations are made for single masonry units based on whole multiples of four inches with consideration given to the various joint thicknesses. Methods are shown for relating unit sizes in fractional multiples of four inches plus mortar joints to the grid pattern. Suggestions for standardization of unit sizes are proposed to obtain maximum simplification and corresponding economy to meet postwar construction requirement

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1943.tb15218.x

出版商:Blackwell Publishing Ltd    

年代:1943

数据来源: WILEY