摘要:

AbstractThe emulsifying powers of various water‐soluble cellulose ethers for mineral and vegetable oils are compared. The advantages of mixtures of sodium carboxymethyl cellulose with other water‐soluble cellulose ethers in producing improved emulsions with reduced foam are shown. Consideration is given to the relative interfacial tensions of methyl ethyl cellulose and sodium carboxymethyl cellulose and to the effects of temperature and hydrogen ion concentration on emulsions prepared from t

ISSN:0368-4075    

DOI:10.1002/jctb.5000681201

出版商:John Wiley&Sons, Ltd    

年代:1949

数据来源: WILEY

摘要:

AbstractThe effects of vapour pressure, rate of heating, and thickness of layer on the temperature and ultimate quality of peas driedin vacuoon a heated tray have been studied experimentally. Higher temperatures and rates of heating than were formerly deemed advisable hive given good results.

ISSN:0368-4075    

DOI:10.1002/jctb.5000681202

出版商:John Wiley&Sons, Ltd    

年代:1949

数据来源: WILEY

摘要:

AbstractThe apparent constants of equilibrium and velocity of the glucose + sulphurous acid reaction were measured under various conditions at 20° c. It was found that: (I) the value of the apparent equilibrium constant is mainly a function ofpH; it is lowest betweenpH, 3 and 5·5 and increases rapidly in more acid or more alkaline regions. Changes in concentration of the reactants (glucose = 1‐40 g./100 ml.; SO2= 130‐3500 mg./l.) seem to haw only a minor influence; (2) the apparent velocity constants of decomposition and of addition are functions of thepHonly.The almost complete parallelism between the dependence of these values uponpHin the case of the bisulphite compounds of both glucose and benzaldehyde suggests the same reaction mech

ISSN:0368-4075    

DOI:10.1002/jctb.5000681203

出版商:John Wiley&Sons, Ltd    

年代:1949

数据来源: WILEY

摘要:

AbstractChlorinated rubbers containing from 1 to 17% of chlorine have been prepared by direct chlorination, at ordinary temperature, of crèpe rubber dissolved in carbon tetrachloride. It has been found that these products retain, to a greater or lesser degree, rubber‐like properties and are capable of hot or cold vulcanization with or without the addition of vulcanizing agents. The resulting vulcanizates have been shown to be considerably more resistant to the swelling action of solvents, and also to the action of chlorine, than corresponding products prepared from crèpe rubber. The resistance to swelling agents increased with increase of combined chlorine content; tensile strength and elasticity, however, decreased with increasing chlorine content. As expected, hardness increased with increase of chlorine content and vulcanizates from derivatives containing more than 10% combined chlorine were not sufficiently rubber‐like to warrant many experiments. It was found that fully Chlorinated rubber was compatible with partially chlorinated rubber and addition of the former was necessary for vulcanizates to pass the Post Office flame test for c

ISSN:0368-4075    

DOI:10.1002/jctb.5000681204

出版商:John Wiley&Sons, Ltd    

年代:1949

数据来源: WILEY

摘要:

AbstractMeasurements have been made of the linear rate of the self‐propagating reaction and of the heat of this reaction in compressed binary solid mixtures of an oxidizing and a reducing agent. The thermochemical results have been used to draw conclusions about the chemistry of the reactions involved and about the maximum temperatures reached during burning. The dependence of the rate of reaction on the heat it evolves is discussed, and an explanation given of the fact that the rate usually reaches its maximum at a higher (and never at a lower) percentage of reducing agent than that at which the heat of burning has its greatest valu

ISSN:0368-4075    

DOI:10.1002/jctb.5000681205

出版商:John Wiley&Sons, Ltd    

年代:1949

数据来源: WILEY

摘要:

AbstractThePittosporaceaeis one of the smaller plant families and the typical genusPittosporumincludes most of the species, some seventy of which arc distributed in New Zealand, Australia, East Indies and Asia. It has been reported that various species of this genus have aromatic odours due to the essential oils they contain, bur apparently there is published information concerning only four of them,P. resiniferum,1P. eugeniodes,2P. undulatum,3andP. Pentandrum.4The essential oils of the first two containn‐heptane andn‐nonane respectively, the her to the extent of 60%. It seemed of interest to ascertain whether the oils of this genus might be divided into two classes, one giving normal plant constituents and the other features by the presence of paraffins and hydrogenated terpenes. To this end, a comparison of the New Zealand species is being undertaken and the oil ofP. renuifoliumis the second to be chemically exami

ISSN:0368-4075    

DOI:10.1002/jctb.5000681206

出版商:John Wiley&Sons, Ltd    

年代:1949

数据来源: WILEY

摘要:

AbstractThe flavour of bacon is usually much less salty than would be expected on the basis of the salt‐content. This is expressed by an “availability index” which is the ratio of the salty flavour observed, to that of a solution containing the same percentage of salt as the bacon, reckoned on fresh weigh. The availability index seems to be an expression of the muscular structure, since it is similar in symmetrical pairs of muscles on opposite sides of a pig, and is largely independent of the quantity of salt added to the meat. Because the availability increases with juiciness, it is suggested that the intensity of salty flavour depends on the speed at which salt is liberated in the mouth on chewing bacon. Juiciness increases with decreasingpHin muscles; hence the availability of salt increases with acidity in bacon. A bacon ofpH6·2 might perhaps contain twice as much salt as one ofpH, 5·3, without tasting more salty. Besides thepH, other characters such as toughness are probably i

ISSN:0368-4075    

DOI:10.1002/jctb.5000681207

出版商:John Wiley&Sons, Ltd    

年代:1949

数据来源: WILEY

摘要:

AbstractThe application of a highly efficient fractionating column to the analysis of essential oils has been studied through the use of a spiral gauze column in the re‐examination of the essential oil of Libocedrus bidwillii (New Zealand Cedar). The following fifteen constituents have been separated.l‐x‐pinene (24 ·8%);d‐sabinene (3·3%); myrcene (2·7%); ketone (C10H16O) (3·7%); limonene and dipentene (7·4%);p‐cymene (3·4%); terpinolene (0·7%) terpinen‐4‐01 (1·2%); unidentified tricyclic sesquiterpene (1·6%); unidentified sesquiterpene (3·7%); caryophyllene (3·0%); γ‐curcumene (18·4%);d‐cadinene (2·7%); green oil (5·8%); and ta

ISSN:0368-4075    

DOI:10.1002/jctb.5000681208

出版商:John Wiley&Sons, Ltd    

年代:1949

数据来源: WILEY

摘要:

AbstractInformation is given as to the rates of peroxidation of diethyl ether and di‐isopropyl ether under normal laboratory conditions of storage, both with and without inhibitors. Di‐isopropyl ether peroxidizes in daylight at least twice as rapidly, and in the dark several times as rapidly, as diethyl ether. By storing di‐isopropyl ether over 20% caustic soda the ether layer can be maintained almost free from peroxide. Anti‐oxidants effectively protect di‐isopropyl ether for limited periods. Diethyl ether can be protected from peroxidation by storage in presence of iron, and can be largely protected merely by storage in the dark.It is proposed in this paper to review briefly the more recent literature dealing with the peroxidation and avoidance of peroxidation of diethyl and di‐isopropyl ethers and to record our own observations under both

ISSN:0368-4075    

DOI:10.1002/jctb.5000681209

出版商:John Wiley&Sons, Ltd    

年代:1949

数据来源: WILEY