ISSN:0021-8871    

DOI:10.1002/jctb.5010131010

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

摘要:

AbstractConditions of agitation strongly affect the recovery of medium rank coal by flotation with oil as collector. As long as collision between coal particles and oil droplets is not prevented by repulsion of the electrical double layers, the effect of agitation is to spread the oil at the coal‐water interface. To remove ambiguities due to the properties of the frothing agent present, experiments on the effects of surface‐active materials on the ease of spreading of the oil were carried out in a special cell with no froth present. The surface‐active reagents improve the distribution of the oil because they lower the oil‐water interfacial tension. Some aromatic materials such as cresylic acid cause similar lowering without making it possible for the oil to spread as readily as when aliphatic reagents a

ISSN:0021-8871    

DOI:10.1002/jctb.5010131001

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

摘要:

AbstractEmpirical relationships commonly used for the prediction of liquid diffusivity data are shown to be unreliable for aqueous solutions of solid solutes. An interferometric technique suitable for diffusivity measurement in such solutions is described. For the system ammonium dihydrogen phosphate‐water over the temperature range 15–50° diffusivities can be estimated from the relationshipDζ × 108= 4.7 + 0.16θThe activation energy for diffusion in near‐saturated solutions over this temperature range is ∼10

ISSN:0021-8871    

DOI:10.1002/jctb.5010131002

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

摘要:

AbstractArising out of the dependence of gas—liquid chromatography on solubility in a manner previously described, the solubilities of five vapours have been measured in a non‐polar solvent and in a polar solvent, both of low vapour pressure, under conditions of dilute solution and over a range of temperatures.The results have been used in the application of a theory which illustrates the action of dilute solutions of vapours in liquids by means of a mechanical model based on the potential energy of attraction, the kinetic energy of vibration, and a probability distribution function.A method is examined in the Appendix in which a conventional temperature‐entropy diagram of the kind used by steam engineers is applied to represent the process of desorbing solutes from solu

ISSN:0021-8871    

DOI:10.1002/jctb.5010131003

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

摘要:

AbstractAs the quantity and nature of the non‐aromatic material in coals is uncertain, the dehydrogenation of coals has been reinvestigated.Aromatic hydrocarbons, unlike phenolic compounds and compounds containing ‘hydroaromatic’ groups attached to aromatic nuclei, could not be dehydrogenated by sulphur below 200°. It was not possible to predict whether the amount of ‘hydroaromatic’ material in coals might be estimated from their treatment with sulphur.The extent of the dehydrogenation of two coals (rank 902 and 401) with sulphur, and hence the amount of ‘hydroaromatic’ material linked to aromatic nuclei, was estimated from the change in the ratio of the infra‐red absorption at 1430 cm.−1to that at 1600 cm.−1Firmer estimates were obtained by dehydrogenating the coals by successive treatment withN‐bromosuccinimide and alcoholic potassium hydroxide. It was concluded that, in agreement with the contentions of the Indian school, 16 ± 2% and 11 ± 2% respectively of the carbon in the coals of rank 902 and 401 was ‘hydroaromatic’ and linked to aromatic nuclei. The manner of the dehydrogenation of the coals by sulphur was considered in some detail and, it being assumed that the above ‘hydroaromaticities’ were correct, it was suggested that the two coals contained few methylene groups which could not be dehydrogenated, and also that the non‐aromatic materials in both coals consisted mainly of ‘hydroaromatic’ me

ISSN:0021-8871    

DOI:10.1002/jctb.5010131004

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

摘要:

AbstractThe series of dehydrogenated coals previously prepared1by treating a 902 rank and a 401 rank coal with sulphur have been pyrolysed in a Gray‐King furnace to 600°. The variations in the yields of products have been compared as functions of the changes in the structure of the coals produced by the previous chemical dehydrogenation. The results obtained confirm the ‘hydroaromaticities’ previously deduced for the two coals and support the interpretation of the manner in which the coals reacted with sulphur. Furthermore, it is shown that when the two original coals were pyrolysed:All the acetylatable hydroxyl groups in the coals formed water,Both the ethane and the ethylene evolved derived from the ‘hydroaromatic’ parts of the coals,Tar was evolved by the disruption of the ‘hydroaromatic’ material which linked the aromatic nuclei in the coals,On the other hand, much of the ‘hydroaromatic’ material dehydrogenated to give an extended aromatic network which remained in the char,The hydrogen liberated by the dehydrogenation of the ‘hydroaromatic’ material was essential to many of those reac

ISSN:0021-8871    

DOI:10.1002/jctb.5010131005

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

摘要:

AbstractA series of samples of oxidised wheat starch was prepared by treating the starch with varying amounts of aqueous sodium hypochlorite, extent of oxidation being followed by estimation of carboxyl and of carbonyl content of each sample; viscosity changes on heating with water were followed by means of the Brabender Amylograph, and paste viscosities at 40° were also determined. The results were compared with those obtained from a commercial sample of oxidised maize starch

ISSN:0021-8871    

DOI:10.1002/jctb.5010131006

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

摘要:

AbstractUtilising a visualPVTcell, experimental values have been established for the critical temperatures and critical pressures of five mixtures containing ethane, propane and n‐butane, and of two mixtures containing propane and n‐butane. The results are extended by use of experimental critical values reported in the literature for the ethane‐propane, ethane‐n‐butane, and propane‐n‐butane binary systems; a unique graphical technique is applied to generate triangular composition diagrams containing parameters of critical temperature and pressure. These diagrams accurately establish the critical point of ethane‐propane‐n‐butane mixtures over the entir

ISSN:0021-8871    

DOI:10.1002/jctb.5010131007

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

摘要:

Abstract1,1,2‐Triphenyl‐2‐tolylethylene is oxidised by chromic oxide in acetic anhydride medium to give 1,2‐epoxy‐1,1,2‐triphenyl‐2‐tolylethane with fission products. A tentative explanation of the stability of such epoxides is given. Aqueous chromic acid oxidation brings about oxidative fission of the double bond. The ultra‐violet absorption spectrum of triphenyl(tolyl)ethyl

ISSN:0021-8871    

DOI:10.1002/jctb.5010131008

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

ISSN:0021-8871    

DOI:10.1002/jctb.5010131009

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY