摘要:

AbstractAttempts have been made to analyse data from rectification in a wetted‐wall column in terms of postulated equations for film values of the height of a transfer unit (HTU) values. Discrepancies found in some of the correlations are no greater than are to be expected from our lack of knowledge of physical characteristics of the binary mixtures, notably of the diffusion coefficient in the liquid phas

ISSN:0021-8871    

DOI:10.1002/jctb.5010010201

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

摘要:

AbstractData are presented which lead to the conclusion that the liquid‐film resistance was the controlling resistance in rectification of a binary system carried out in a particular packed column. This confirms the conclusion reached by other workers on similar packed column

ISSN:0021-8871    

DOI:10.1002/jctb.5010010202

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

摘要:

AbstractThe original method employed by Wilson to eliminate the use of thermocouples embedded in the tube wall in evaluating the heat‐transfer coefficient of the condensing vapours is not fundamentally sound. A modified method on a more rigorous basis is presented.It has been demonstrated theoretically that the heat‐transfer coefficient of a condensing vapour is a function of rate of heat only. The proposed method consists in varying the rate of flow of cooling water inside the condensing tube and the over‐all temperature difference to obtain the heat‐transfer coefficients at a constant rate of heat‐transfer. The over‐all temperature drop is varied by changing the pressure in the vapour space. The film coefficient is then calculated from the intercept of a plot of δT/qagainst 1/(1 + 0.011t) V0.8.The heat‐transfer coefficients of trichloroethylene, bromobenzene, nitromethane andn‐hexyl alcohol have been experimentally determined by the proposed method. The theory of the method was confirmed by plottingh0againstq; the slope was equal to‐1/3.The heat‐transfer coefficients predicted from Nusselt's equation agreed with those determined experimentally for trichloroethylene and bromobenzene, but not with those for nitromethan

ISSN:0021-8871    

DOI:10.1002/jctb.5010010203

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

摘要:

AbstractExtension of the general method for the preparation of sulphonylcyanamides by the interaction of arylureas and aromatic sulphonyl chlorides has givenp‐aminobenzenesulphonylphenylcyanamide by two routes. A number of related substituted sulphonamides of this type are also described. Migliardi and Tappi's claim to have obtained sulphonylureas fromas‐diarylurea and arylsulphonyl chlorides could not be substantiated, the expected diarylcyanamides being obtained instead under the conditions of the present synthesis.Attempts to extend to arylsulphonylarylcyanamides the general reaction of converting cyanamides to thioureas by the addition of hydrogen sulphide were unsuccess

ISSN:0021-8871    

DOI:10.1002/jctb.5010010204

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

摘要:

AbstractThe doping of sprayed aluminium with ethyl silicate has been found to give a heat‐resistant coating which needs no heat treatment before putting into service. This coating is compared with aluminizing, and the relative protection given by these two coatings to mild steel from 700° to 950° C. has been determi

ISSN:0021-8871    

DOI:10.1002/jctb.5010010205

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

摘要:

AbstractGuanylazide nitrate (I) interacts with hydrazine, the reaction products varying with molar ratio of hydrazine to azide. With equimolecular quantities of reactants, cyanamide, hydrazoic acid, 5‐amino‐tetrazole (III) and some aminoguanidine are formed, but with higher proportions of hydrazine, diaminoguanidine and triaminoguanidine are the chief products.Simple and rapid preparative methods for diaminoguanidine nitrate and triaminoguanidine nitrate are described.Benzylideneaminoguanidine, unlike aminoguanidine, does not undergo hydrazinolysis, but in a replacement reaction gives benzylideneazine and aminoguanid

ISSN:0021-8871    

DOI:10.1002/jctb.5010010206

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY

ISSN:0021-8871    

DOI:10.1002/jctb.5010010207

出版商:John Wiley&Sons, Ltd    

年代:1951

数据来源: WILEY