摘要:

AbstractDuring the autocatalytic oxidation of esters of oleic acid (9‐cis‐octadecenoic acid) and petroselinic acid (6‐cis‐octadecenoic acid) at moderate temperatures, volatile aldehydes are produced. They consist mainly of the four aldehydes predicted by the α‐methylenic free‐radical chain theory. Also significant amounts of lower ‘unexpected’ aldehydes are present; they are likewise produced during hydroperoxide decomposition in the absence of oxygen. ‘Higher’ aldehydes are virtually absent.The conversion of methyl petroselinate hydroperoxide on a Celite/dinitrophenylhydrazine‐hydrochloric acid column yields the DNPHs of aldehydes, aldehyde esters and conjugated keto‐octadecenoates. The aldehydes are the same as the volatile aldehydes produced during autoxidation; and it is concluded therefore also the lower aldehydes are formed directly from the hydroperoxides.The formation of lower aldehydes can be explained by assuming the presence of bishydroperoxides as minor primary oxidation products, formed in an intramolecular chain‐propagation step. An explanation is suggested for the relatively small yield of aldehydes during hydroperoxide decomposition under anaerobic conditions, in comparison with the amou

ISSN:0021-8871    

DOI:10.1002/jctb.5010150601

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractThe formation of conjugated diene hydroperoxide during the early stages of the autoxidation of ethyl linoleate in air and pure oxygen has been studied at 22° and 50°. The published rate equations which have been proposed for the autoxidation of olefinic systems have been integrated and the experimental results fitted to the integrated equations. In order to obtain a reasonable fit to the data, the decomposition of hydroperoxide must be taken into account. The rate constants and activation energies associated with the formation and decomposition of ethyl linoleate hydroperoxide have been obtained and are compared with previously published value

ISSN:0021-8871    

DOI:10.1002/jctb.5010150602

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractA comparison made between results of exposure tests of mild steel specimens to the waters of the Thames estuary for 2 years with earlier results for 1 year showed a general reduction in corrosion rate, for both weight‐loss and pitting. There is evidence that the contribution towards total corrosion from microbiological attack is less important than that from the action of aerobic saline water. The relation between corrosion rates and the position of exposure sites along the estuary has remained substantially unaltere

ISSN:0021-8871    

DOI:10.1002/jctb.5010150603

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractThis paper presents an empirical method of predicting the drying times of porous‐granular and fibrous materials in a hot‐air tray dryer under various conditions of tray loading, air temperature, humidity and velocity. The method uses results obtained from a series of drying tests planned as a fractional three‐level factorial experiment to examine the effects of the above four drying variables on the drying times of the various materials tested. The method is illustrated by application to porous‐ceramic granules, 1/4 in. dia. × 1/4 in. long, coke, 3/8–1/4 in. mesh (porous‐granular materials) and to brewers' spent grain (fibrous material); predicted drying times were within ±16% of the experi

ISSN:0021-8871    

DOI:10.1002/jctb.5010150604

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractThe application of the empirical method of predicting drying times of porous granular and fibrous materials in a tray dryer described in Part I is extended to predicting the drying times of these materials in a through‐circulation dryer. The predicted drying times in the through‐circulation dryer were within ±10% of the experimental va

ISSN:0021-8871    

DOI:10.1002/jctb.5010150605

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractVarious modifications of the method of centrifuging have been critically studied. The correction for interstitial water is complicated by finite angles of contact, compression of the resin bed, and slow attainment of equilibrium. The use of a non‐ionic detergent of high molecular weight has led to a procedure which eliminates errors caused by these effects, and which is convenient and rapid. It can be adapted to the measurement of the volume of macropores in macroporous resin

ISSN:0021-8871    

DOI:10.1002/jctb.5010150606

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

ISSN:0021-8871    

DOI:10.1002/jctb.5010150607

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

ISSN:0021-8871    

DOI:10.1002/jctb.5010150608

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY