摘要:

AbstractThe problem of satisfying requirements for the distillation of mixtures containing several components is discussed, and the general solution is outlined.A routine method is described which will lead to a particular solution in the absence of information on the number of theoretical plates or the feed plate location.

ISSN:0021-8871    

DOI:10.1002/jctb.5010101202

出版商:John Wiley&Sons, Ltd    

年代:1960

数据来源: WILEY

摘要:

AbstractThe pyrolysis of diborane has been studied in single‐ and multi‐pass flow systems to determine the optimum conditions for its conversion to pentaborane.In a single‐pass flow system the products consisted of tetraborane, dihydropentaborane (B5H11), pentaborane (B5H9), decaborane and undesirable non‐volatile solid hydrides. The most economical conversion of diborane to pentaborane was obtained under the following conditions: temperature 250°, flow rate 400 c.c./min. and ratio of diborane/hydrogen 1 : 5 when 15·1% of the diborane was converted into pentaborane, 4·4% to solid hydrides and 80% recovered.In multi‐stage reactors designed on the basis of single‐pass experiments, the best yield of pentaborane was obtained in a 12‐unit reactor operating at 240°, flow rate 400 c.c./min. and ratio diborane/hydrogen 1 : 5. Under these conditions 57·0% of the diborane was converted into pentaborane, 14·1% to solid hydrides and 29·0% was recovered unchanged.Rate expressions are developed for the disappearance of diborane and activation energies calculated.The mechanism of the formation of pentaborane and dec

ISSN:0021-8871    

DOI:10.1002/jctb.5010101203

出版商:John Wiley&Sons, Ltd    

年代:1960

数据来源: WILEY

ISSN:0021-8871    

DOI:10.1002/jctb.5010101208

出版商:John Wiley&Sons, Ltd    

年代:1960

数据来源: WILEY

ISSN:0021-8871    

DOI:10.1002/jctb.5010101204

出版商:John Wiley&Sons, Ltd    

年代:1960

数据来源: WILEY

摘要:

AbstractWhen stainless steel is immersed in H.T.P. an oxide film is formed on the surface of the metal. The rate of formation, composition and stability of this film have been investigated by chemical analysis and electrometric methods. The film consists mainly of oxides of iron and at 30° it grows to a fairly constant thickness of 3×10−6cm. in 3–4 weeks. The compatibility of stainless steel with H.T.P. is explained in terms of the solubility and catalytic activity of the main constituents of stainless

ISSN:0021-8871    

DOI:10.1002/jctb.5010101205

出版商:John Wiley&Sons, Ltd    

年代:1960

数据来源: WILEY

摘要:

AbstractBreak‐through curves for the exchange of Na+ions in 0·1 n‐NaCl in glycerol‐water mixtures for H+ions in a fixed bed of Dowex‐50‐resin have been determined for Reynolds numbers from 0·01 to 2. Solutions containing up to 75% by vol. of glycerol and having viscosities up to 30 centipoise at 25° were used. Some measurements were also made on 0·1 n‐NaCl in ‘Polycell’ solutions in water. Small concentrations of this substance increase the viscosity of the system considerably with little effect on the ionic diffusivity. Effluent compositions and ionic diffusivities were determined by electrical conductivity. The total resistances to mass‐transfer were calculated from the slopes of the break‐through curves and values of the liquid film resistance estimated by the method of Gilliland&Baddour.2The observed values of the liquid film coefficient could be correlated with flow rate, solution viscosity, and ionic diffusivity by the equation:kLD2/

ISSN:0021-8871    

DOI:10.1002/jctb.5010101206

出版商:John Wiley&Sons, Ltd    

年代:1960

数据来源: WILEY

摘要:

AbstractThe film capacities and weight gains of specimens of Kroll zirconium exposed to steam and to dry oxygen at 325° have been compared. The results show that the initial growth of uncracked oxide films is more rapid in steam, and that subsequent film cracking is also more severe, presumably as a result of effects due to hydrogen.Films on Van Arkel zirconium are more resistant to cracking in both steam and oxygen.At a late stage of oxidation in both steam and oxygen the film capacities reach constant values indicating that the mean thickness of the protective part of the film in each case also tends to a constant value. However, a comparison of the oxidation rates at this stage shows some discrepancies in relation to the initial oxidation rates and a modified picture of film growth and breakdown is proposed

ISSN:0021-8871    

DOI:10.1002/jctb.5010101207

出版商:John Wiley&Sons, Ltd    

年代:1960

数据来源: WILEY

ISSN:0021-8871    

DOI:10.1002/jctb.5010101201

出版商:John Wiley&Sons, Ltd    

年代:1960

数据来源: WILEY