摘要:

Further studies on the isometric form of hydrated tricalcium aluminate are reported. These include methods of preparation, crystalline forms, X-ray diffraction pattern, and determinations of solubility and density. The products formed when the hexagonal form of hydrated tricalcium aluminate is dehydrated at definite vapor pressures of Water at 21 °C., were studied. The density, refractive indices, heats of solution in HCl.200 H2O, and the X-ray diffraction patterns of several probable hydrates were determined. The experimental evidence given indicates that hydrates of 3CaO.Al2O3having 6, 8, 91/2, 101/2, and 12 moles of water are formed, but that the water in excess of 8 moles is very loosely held and that its removal does not materially affect the crystal structure. The exact composition of some of the higher hydrates requires confirmation.

ISSN:1923-4287    

DOI:10.1139/cjr29-012

出版商:NRC Research Press    

年代:1929

数据来源: NRC

摘要:

The greenish-yellow discoloration of the ventral side ofHippoglossus hippoglossus(Linn.) is described. This discoloration is often accompanied by softness of the flesh, which greatly reduces the value of the fish. The color-producing organism was isolated and identified asPseudomonas fluorescens; its characteristics are given. Examination of materials from which the halibut might be infected revealed that the ultimate source of the organism was the fresh-water ice in which the fish were packed after being caught. Some sixteen other organisms, isolated from freshly caught living halibut and from sea water, are fully described.

ISSN:1923-4287    

DOI:10.1139/cjr29-013

出版商:NRC Research Press    

年代:1929

数据来源: NRC

摘要:

A small-scale method was first developed in which the degree of chlorination of methane to methyl chloride could be determined by analysis of the resulting gases. The optimum conditions so determined were then applied on a scale which permitted the isolation and measurement of the products. A yield of 80% or better was obtained when using as a catalyst partially-reduced cupric chloride and passing moist nitrogen, methane and chlorine in the ratios of 70:7:1 at 450 °C. It was found that the proportion of chlorine could be more than doubled when 8% of hydrogen was present in the methane. Under such conditions the chlorine was completely utilized and only methyl chloride and hydrogen chloride were formed. The yield of isolated methyl chloride obtained was nearly 80% and this could be increased by operating on a larger scale. The same catalyst was successfully used in the chlorination of methane to carbon tetrachloride. A yield of 90% was obtained, with complete utilization of the chlorine. The chlorination of ethane to ethyl chloride, with a yield of at least 75% was also shown to be possible.

ISSN:1923-4287    

DOI:10.1139/cjr29-014

出版商:NRC Research Press    

年代:1929

数据来源: NRC

摘要:

The addition of saltpetre (potassium nitrate) to colored cheese is shown to produce discoloration which is unevenly distributed and which becomes very marked with age. Fresh nitrated cheese gives a positive test for nitrates; on aging, the nitrite is decomposed. Nitrate-reducing organisms have been isolated from all discolored cheese. These, when inoculated into sterilized milk with annato and potassium nitrate, produce the typical flesh-colored or vinaceous-brown discoloration. Commercial saltpetre may contain nitrate-reducing organisms, as may also the water used in diluting rennet or cheese colors.Pseudomonas fluorescens, one water organism capable of producing the discoloration, was isolated. It is recommended that the use of saltpetre in cheese be immediately discontinued.

ISSN:1923-4287    

DOI:10.1139/cjr29-015

出版商:NRC Research Press    

年代:1929

数据来源: NRC

摘要:

In this investigation a series of new iso-urea ethers has been prepared by the general reaction of addition of alcohols to cyanamide in the presence of dry hydrogen chloride. Where the hydrochlorides of the iso-ureas were difficult to isolate and purify, conversion to the salicylates gave excellent results. The new iso-ureas were further characterized by condensing them with methyl malonate to form iso-urea salts of 2-alkoxy-barbituric acids, from which the acids themselves could be easily liberated by the addition of dilute mineral acid. A few open-chain acyl derivatives were also prepared.

ISSN:1923-4287    

DOI:10.1139/cjr29-016

出版商:NRC Research Press    

年代:1929

数据来源: NRC

摘要:

This paper describes the methods employed in the use of expansion measurements as a means of studying the action of sulphates on Portland cement, and on Portland cement mortars. Experimental data are given dealing with the reproducibility of the expansion measurements and the relation between expansion and loss of tensile strength of mortars. Results obtained with standard sand mortars and graded sand mortars of varying richness of mix prepared from cements which differ in their resistance to sulphate action are presented.

ISSN:1923-4287    

DOI:10.1139/cjr29-017

出版商:NRC Research Press    

年代:1929

数据来源: NRC