摘要:

AbstractIn a previous communication,1the seasonal variation in chemical constitution ofLaminaria cloustoniover a period of two years was given. The present paper outlines the seasonal variation in ash, crude protein, iodine, mannitol, laminarin and alginic acid ofLaminaria digitatafor the same period. In this case the samples were taken from two different localities, to find the effect of different degrees of exposure on the chemical constitution.

ISSN:0368-4075    

DOI:10.1002/jctb.5000670501

出版商:John Wiley&Sons, Ltd    

年代:1948

数据来源: WILEY

摘要:

AbstractIn previous communications,1, 2the seasonal variation in chemical constitution of the laminarialescloustonianddigitataover a period of two years was recorded. The present paper outlines the seasonal variation in ash, crude protein, iodine, mannitol, laminarin and alginic acid ofL. saccharinafor the same period. As withL. digitata, the samples were taken from two different localities, to find the effect of different degrees of exposure on the chemical constitution, and the stipes and fronds have been analysed separately. Samples of the annualsaccorhiza bulbosahave also been analysed.

ISSN:0368-4075    

DOI:10.1002/jctb.5000670502

出版商:John Wiley&Sons, Ltd    

年代:1948

数据来源: WILEY

摘要:

AbstractThe Wurtz‐Fittig reaction has been studied as a method for the industrial preparation of organo‐substituted silanes from silicon tetrachloride or silicochloroform. Since the principal products are SiR, or SiHR, compounds the reaction is not as flexible as alternative methods for the preparation of organo‐silicon compounds. The results show the reaction to be suitable for the laboratory preparation of alkyl silanes, but not for alkyl silanes, or nuclear substituted alkyl silanes. Evidence has been obtained for the formation of alkyl chlorosilanes as intermediate products, and of hexa‐alkyl disilanes as by‐products, during the preparation of alkyl silanes. The reaction will be difficult to adapt to large‐sc

ISSN:0368-4075    

DOI:10.1002/jctb.5000670503

出版商:John Wiley&Sons, Ltd    

年代:1948

数据来源: WILEY

摘要:

AbstractThe retrograding properties of the C.W. Sol. and H.W. Sol. fractionsAs previously, 2, 3, 4, 5, 6 these fractions me defined as follows: C.W. Sol.‐‐‐Material soluble in cold water (room temperature).of potato starch have been investigated under varying conditions of temperature and concentration and are qualitatively not unlike those of the wheat starch fractions investigated previously.1The quantitative differences between the retrograding properties of the two sets of fractions appear to be governed by (a) their contents of amylose and amylopectin and (b) the differences in the nature and distribution of the small quantities of phosphorus present in the two sta

ISSN:0368-4075    

DOI:10.1002/jctb.5000670504

出版商:John Wiley&Sons, Ltd    

年代:1948

数据来源: WILEY

摘要:

AbstractThe procedure to be described has been found to be useful in the spectrographs determination of composition by the method in which the log, ratio of deflection is plotted against % content (or log. % content), no intensity calibration being carried out. Essentially the procedure consists of using two line pairs for each determination, one on the positive and the other on the negative side of log. ratio 0·000 Where the log. ratio is reasonably near zero it is, of course, unnecessary to read two line pairs. By placing a straight edge through the log. ratio points on the corresponding composition curves and reading off the composition corresponding to the log. ratio 0·000 on this straight line a weighted average is obtained which corrects for plate response, thus giving a better accuracy than that obtained by the use of individual line pairs and log. ratios uncorrected for intensity by plate characteristic curve techniqu

ISSN:0368-4075    

DOI:10.1002/jctb.5000670505

出版商:John Wiley&Sons, Ltd    

年代:1948

数据来源: WILEY

摘要:

AbstractA simple nomographical method of evaluation of minor constituents is given which, provided that the density values all fall on the straight line portion of the H&D curve of the emulsion used, is independent of gamma variation. When the nomograph is drawn, not only docs it correct for changes in gamma across one plate, but also from plate to plate ofanytype, thus obviating the need for repeated standardization.

ISSN:0368-4075    

DOI:10.1002/jctb.5000670506

出版商:John Wiley&Sons, Ltd    

年代:1948

数据来源: WILEY

摘要:

AbstractA comparative study has been made of the jellying properties of tamarind seed polyose with those of certain fruit pectins in presence of varying amounts of sucrose and acid and it is shown that, with a concentration of the polyose about half that of fruit pectins, firm jellies are obtained under otherwise comparable conditions. The possibility of improving the texture of the polyose‐sugar‐acid jelly by pretreatment with mild acid or alkali or by methylation is indica

ISSN:0368-4075    

DOI:10.1002/jctb.5000670507

出版商:John Wiley&Sons, Ltd    

年代:1948

数据来源: WILEY

摘要:

AbstractIn the soupfin shark the iodine value of the liver oil of the mature fish tends to increase with increase in the oil content of the liver. Determination of the component fatty acids of a composite sample of liver oil from females in fat condition and another from thin (gravid) females showed that this effect is due to the greater degree of unsaturation of the C16, C18, C20and C22acids in the fat fish. The component fatty acids of a composite sample of foetus liver oil were also examined. It is suggested that there may be a transference of highly unsaturated C18, C20and C22acids from the female to the foetus during gestation. The unsaponifiable fractions of five soupfin shark liver oils were quantitatively examined. In the mature fish, vitaminA, α‐glyceryl ethers and sterols are major components of the unsaponifiable fraction, whereas in the foetus, sterols predominate. Evidence for the presence of fatty alcohols in the unsaponifiable fraction of the liver oils from both the foetus and the mature fish is present

ISSN:0368-4075    

DOI:10.1002/jctb.5000670508

出版商:John Wiley&Sons, Ltd    

年代:1948

数据来源: WILEY

摘要:

Abstract“The use of monoreactive phenol alcohols as models for the general polymerization of phenolic resins (as is commonly suggested) leads to the conclusion that such resins will contain in the earlier stages of condensation a considerable proportion of dibenzyl ether linkages. It may be concluded from a partial theoretical analysis that whatever the exact reaction mechanism this conclusion is of doubtful validity, and the analysis is supported by data on the polymerization of nitro‐ and chloro‐sali

ISSN:0368-4075    

DOI:10.1002/jctb.5000670509

出版商:John Wiley&Sons, Ltd    

年代:1948

数据来源: WILEY

摘要:

AbstractThe fatty oils which form about 40% of the dried seeds of West Indian grape fruits, oranges and limes have been studied with respect to their component acids and glycerides. The mixed fatty acids of each seed oil arc broadly similar in their content of 23‐25% of palmitic, 5‐10% of stearic, nearly 40% of Unoleic and about 20‐25% of oleic acid, with in addition a few per cent of linolenic acid. Apart from the last‐named acid, there is considerable resemblance between the component acids of theCitrusseed oils and those of cottonseed oil. This resemblance extends also to the constituent mixed glycerides of the oils. TheCitrusseed oils are of good quality in the raw condition and are readily refined and deodorized to give oils of high edible quality. The latter, in view of the presence of some linolenic glycerides, would be expected to be more prone to oxidative rancidity than cottonseed oil, but by partial hydrogenation theCitrusseed oils yield soft solid fats which when refined and deodorized could form excellent lard substitutes. The quantities ofCitrusseeds available technically, however, may not be sufficiently large to permit the oils to be of practical interest to the edible fat i

ISSN:0368-4075    

DOI:10.1002/jctb.5000670510

出版商:John Wiley&Sons, Ltd    

年代:1948

数据来源: WILEY