摘要:

The viscosities and densities of crude chlorosulphonic acid – sulphur trioxide mixtures have been determined for compositions between 10 and 70%. The viscosity measurements were carried out at temperatures between 20° and − 40 °C. for those liquids that did not show crystallization over this range. At temperatures at which the complete range of compositions could be investigated, both the density– and viscosity–composition curves exhibit a maximum.

ISSN:1923-4287    

DOI:10.1139/cjr48f-025

出版商:NRC Research Press    

年代:1948

数据来源: NRC

摘要:

Compounds that cause an increase in the knocking tendency of gasolines are of two main types: (1) those such as dichloromethylarsine, cacodyl chloride, and arsenic tribromide, which counteract the effect of antiknock compounds present, and (2) those which, in addition, have some effect on the base stock, such as chloropicrin, bromopicrin, and bromine. Halogens, nitrites, nitro compounds and elements of Group V add to the pro-knock properties of a molecule. A long chain and an asymmetric molecule are effective structures. Pro-knock neutralized the effect of the antiknock but the concentration bore no direct relation to the antiknock concentration. Compounds of the first type showed greatest effect in fuels of high lead susceptibility brought up to a high octane rating with lead tetraethyl from a low octane base stock. They were similarly effective in counteracting iron carbonyl, but had no effect on aniline. Compounds of the second type effectively counteracted aniline, and when added to Diesel fuels showed a marked increase in the cetene number.

ISSN:1923-4287    

DOI:10.1139/cjr48f-026

出版商:NRC Research Press    

年代:1948

数据来源: NRC

摘要:

It should not be possible, according to the nuclear theory of ignition, stated in Part IV, to obtain ignition in the body of a gaseous combustible mixture by any method of heating if it remain truly homogeneous while the temperature is raised. Such mixtures cease to be homogeneous when heated by sudden compression to the temperatures required for ignition because of the formation of finely divided carbon by pyrolysis of lubricating oil or of hydrocarbon vapor. The finely divided carbon provides nuclear centers of ignition in the gaseous mixture. Ignition due to finely divided carbon produced by pyrolysis of the lubricant is demonstrated by experiments with hydrogen as the fuel for a C.F.R. engine. The usual pre-ignition and severe knocking were obtained when the engine in normal condition was run on hydrogen, and it was impossible, as previously found by others, to use any but weak mixtures even at low compression ratios. When however the combustion space was decarbonized and thereafter maintained reasonably clear of fluffy carbon, hydrogen could be used as the sole fuel at any compression ratio up to the limit of 10:1 possible with the engine, and at any mixture strength ranging from very weak to very rich, while power output varied accordingly. Conversely pre-ignition and combustion knock reappeared when carbon dust was admitted with the combustible mixture.

ISSN:1923-4287    

DOI:10.1139/cjr48f-027

出版商:NRC Research Press    

年代:1948

数据来源: NRC