摘要:

AbstractDifficulty in the removal of calcium carbonate by filtration in the preparation of cyanamide by passage of CO2through an aqueous slurry of the calcium salt, is overcome by dissolution of the salt in an aqueous solution of cyanamide before passage of the CO2. A large laboratory apparatus is described for this process, by which high yields are obtained. Stable solutions of cyanamide of 60% concentration or 95% pure solid material can be prepared which are very convenient for the preparation of cyanamide derivatives, several of which are described.

ISSN:0021-8871    

DOI:10.1002/jctb.5010060301

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractThe preparation of organo‐tin compounds containing a cyanomethyl group attached to the tin atom is described. The formation of the tin—carbon bond occurs through a decarboxylation reaction. Some chemical properties of the cyanomethyltin compounds are gi

ISSN:0021-8871    

DOI:10.1002/jctb.5010060302

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractData on a number of British coals have been examined by the methods of statistical structural analysis and the results are compared with those obtained by van Krevelen on Saar and Lorraine vitrinites.For British coals above 83% carbon the results are similar, but for low‐rank coals, where non‐aromatic structures become important, the techniques applied are inadequate. There is no evidence of a minimum in the curve relating the number of rings per C atom and the rank of the coal. Data showing the change in refractometric increment per aromatic carbon atom with increasing coal rank offer an explanation of the properties of coal. A suggestion has been made that the blackness of coal can be given a qualitative explanation from the range of charge transfer ba

ISSN:0021-8871    

DOI:10.1002/jctb.5010060303

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractA picrate method of determining naphthalene in gas is described with a correction for unsaturated picrate‐forming hydrocarbons. An ultra‐violet method of determining naphthalene and mono‐methylnaphthalenes separately in gas is outlined. A comparison shows that the picrate method gives results agreeing with the total of naphthalene plus monomethyluaphthalenes as determined by the ultra‐violet

ISSN:0021-8871    

DOI:10.1002/jctb.5010060304

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractSeparation of some volatile paraffinic, naphthenic, olefinic and aromatic hydrocarbons by means of gas‐liquid chromatography are described. Stationary liquid phases capable of specifically retarding certain chemical structures are used in the identification of the different types of hydrocarbon. Some generalisations are made on factors affecting separations by gas‐liquid chromatogra

ISSN:0021-8871    

DOI:10.1002/jctb.5010060305

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractThe action of dilute aqueous solutions of representative aniouic, cationic and non‐ionic wetting agents on aluminium has been studied, using London tap‐water and distilled water.Several of the anionic active agents imparted a water‐repellent film to the metal and this afforded protection, with sulphonated castor oil and sodium di‐(2‐ethylhexyl) sulphosuccinate, but not with sodium alkylarylsulphonate or triethanolamine lauryl sulphate.The attack took the form of pitting, the pits being covered with nodules of corrosion product.All cationic agents had some action on the metal, this action being most marked in the case of triethanolamine which appeared to exert a solvent action; the non‐ionic agent had little effect.Many of the specimens immersed in tap water solutions acquired a firm deposit of calcium carbonate crystals.Results have been expressed graphically and mechanism

ISSN:0021-8871    

DOI:10.1002/jctb.5010060306

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

ISSN:0021-8871    

DOI:10.1002/jctb.5010060307

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY