摘要:

AbstractA new method is described for the production of manganous sulphate from low‐grade manganese ores. The ore is first treated with a calculated amount of concentrated sulphuric acid at 200–220° to form manganic and ferric sulphates, and then heated at 500–640° for 90 min. The percentage conversion to manganous sulphate reaches 80, with almost 100% utilisation of sulphur, and contamination with iron is low.An explanation is suggested for the rǒle played by iron in increasing both manganese conversion and efficiency of sulphur uti

ISSN:0021-8871    

DOI:10.1002/jctb.5010140301

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractA method for calculating the pore size distribution from adsorption isotherms on porous solids is described, which is more exact and less tedious to use than some previously described methods. The method of compiling tables for calculation is shown and an example of such a calculation is given.

ISSN:0021-8871    

DOI:10.1002/jctb.5010140302

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractThe increase in the chemical reactivity of nuclear graphite towards air following thermal and r.f.‐activated oxidation has been compared and evidence obtained for an enhanced reactivity following the activated oxidation, without change in surface area. The dependence of reactivity on surface area has also been studied for virgin and thermally oxidised samples and a linear relation found between the two quantitie

ISSN:0021-8871    

DOI:10.1002/jctb.5010140303

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractThe distribution of nitric acid between water and both 20 and 30% v/v solutions of tri‐n‐butyl phosphate in odourless kerosene at 20° and 25° has been studied systematically up to aqueous phase concentrations of 10 moles per litre. An equation is derived to represent the distribution up to aqueous phase concentrations of 4 moles per

ISSN:0021-8871    

DOI:10.1002/jctb.5010140304

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractThe calcination of dolomite has been studied by determining the changes in specific surface and phase composition and crystallite size during decompositionin vacuoor in air at a series of temperatures up to 900°.The overall surface activities of the dolimes are correspondingly greater than those of the ordinary limes obtained in previous investigations. The calcium oxide crystallites are similar in size to those in ordinary limes, but the magnesium oxide crystallites are much smaller. This is due mainly to the greater volume decrease associated with the magnesium oxide formation. However, this oxide is correspondingly less active than that from magnesite. Hence, some of its sintering is evidently enhanced by the presence of the calcium oxide.At lower temperatures, i.e., below 700° in air, some of the carbon dioxide evolved inhibits the decomposition by recombining with the newly‐formed calcium oxide; this reduces the surface activity of the product. At higher temperatures, the surface activity is also reduced by impurities with lower melting points generally enhancing sintering of the dol

ISSN:0021-8871    

DOI:10.1002/jctb.5010140305

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractDolomitic lime samples differing widely in surface activity (specific surface, 5–65 m.2g.−1) have been ‘dry’ hydrated by exposure to water vapour at 22° and ‘wet’ hydrated by liquid water at 22° and 95°.In general, the calcium oxide hydrates much more rapidly than the magnesium oxide in the dolimes. During the ‘dry’ hydration of dolime, the calcium hydroxide impedes subsequent hydration of the magnesium oxide. In the ‘wet’ hydrations, changes in surface area and crystal structure resemble those during the separate hydratio

ISSN:0021-8871    

DOI:10.1002/jctb.5010140306

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractCatalytic oxidation of isoquinoline yields phthalimide (major product) and smaller amounts of pyridine and hydrogen cyanide. The reaction mechanism is discussed.

ISSN:0021-8871    

DOI:10.1002/jctb.5010140307

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

摘要:

AbstractA number of fractions have been prepared on a large scale from Ziegler 0·945‐density polyethylene and Phillips 0·96‐density polyethylene. Their physical properties have been compared with those of whole polymers having much broader distributions of molecular weight. It is shown that the main effects of narrowing the molecular‐weight distribution of polyethylene are to lower its density, to reduce its tensile yield strength, probably to increase its impact strength, and (with some reservations) to increase its ultimate elongation. Little change is evident in melt index or folding endurance. The effects on stress‐cracking resistance depend upon the type of polymer being considered. The relationship between yield strength and density is independent of intrinsic viscosity and of intrinsic viscosity dis

ISSN:0021-8871    

DOI:10.1002/jctb.5010140308

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

ISSN:0021-8871    

DOI:10.1002/jctb.5010140309

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY

ISSN:0021-8871    

DOI:10.1002/jctb.5010140310

出版商:John Wiley&Sons, Ltd    

年代:1964

数据来源: WILEY