ISSN:0021-8871    

DOI:10.1002/jctb.5010061009

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractA testing procedure is described which involves a concentration of the solution by foaming, and detection of the gelatin in the foam by means of a modified Zsigmondy gold sol test. Gelatin can be detected, in the presence of large quantities of electrolyte, at concentrations as low as 4 × 10−8g./ml. The method can be made semi‐quantitative and is probably applicable to many other substa

ISSN:0021-8871    

DOI:10.1002/jctb.5010061001

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractLaboratory investigations of the failure of zinc anodes in sea water have shown that the presence of iron in excess of a few parts per million is the cause. No other common impurity is important.Whilst zinc of low iron content is commercially available, difficulty has been experienced in large‐scale production of uncontaminated anodes. Search has therefore been made for elements which when alloyed with the zinc would counteract the effect of iron. It was found that small additions of aluminium to zinc containing 200 p.p.m. of iron produce permanently active anodes. It is shown that the alloying additions refine the grain size of the metal and give a smooth corrosion pattern.The combined effect of silicon and aluminium is being further investigate

ISSN:0021-8871    

DOI:10.1002/jctb.5010061002

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractThe denaturation of arachin at pH 11 and at ionic strengthsI= 1.0, 0.2 and 0.05 has been studied by means of the ultracentrifuge. Change of the arachin component to slowly sedimenting material occurred by way of an intermediate component of sedimentation constant similar to that of the arachin dissociation component. The rate cf disappearance of the arachin component is greater the lower the ionic strength whereas the formation of the intermediate component is favoured at high ionic strengths (e.g., 1.0). A fairly pure sample of this intermediate component has been prepared. The half life (t1/2) of the reaction atI= 0.2 was not found to vary significantly on increasing the protein concentration thirteenfold. The logarithmic plot of protein concentration against time, however, failed to give the straight line expected of a reaction which is first‐order with respect to protein concentration. Possible causes for this seeming discrepancy are discusse

ISSN:0021-8871    

DOI:10.1002/jctb.5010061003

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractThe method of preparation of tetrasodium ethylenediaminetetra‐acetate enclosed in a cellular semipermeable membrane structure of silica is described and the properties of the dried gel in contact with water are discusse

ISSN:0021-8871    

DOI:10.1002/jctb.5010061004

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractA study has been made of the curing of epoxy resins from 2: 2‐bis‐(4‐hydroxyphenyl)propane with phthialic anhydride. It is shown that in all cases an equilibrium is set up in which, after complete reaction of the epoxy groups, there are present anhydride, monoester and hydroxyl groups. The effect of temperature on the content of these groups has been determined and shown to be considerable.On heating cured resins, most of the monoester groups are split off and phthalic anhydride is evolved. A minimum point is obtained in the graph relating loss of weight and amount of anhydride used. The reason for this is discussed. The distribution of the various types of group has been determined in cured resins by chemical methods, which affords a good picture of the structure of resins cured under different condi

ISSN:0021-8871    

DOI:10.1002/jctb.5010061005

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

ISSN:0021-8871    

DOI:10.1002/jctb.5010061006

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractA spectra‐structure correlation chart for phosphorus compounds is presented, and the existing evidence for these correlations is summarized.Powdered phosphate salts absorb in a number of discrete regions which are characteristic of the type of anion present. The use of this data for qualitative identification is discussed, and examples are given of the use of the pressed disc technique for quantitative wor

ISSN:0021-8871    

DOI:10.1002/jctb.5010061007

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY

摘要:

AbstractVarious chromatographic and experimental techniques are described, which have made possible the analysis of samples taken from phenol—formaldehyde reaction mixtures studied over a wide range of conditions. Many of the components have been identified by chromatography with known compounds, theRFvalues of the others have been recorded for information in tabular form.Some of the simpler reactions possibly involved in these condensations have been investigated, allowing a tentative hypothesis to be formed regarding the reaction mechanism involved.The investigation partially clarifies the earlier stages of the reaction although compounds are present, just prior to the resin becoming insoluble, which cannot be identified with any known intermediate

ISSN:0021-8871    

DOI:10.1002/jctb.5010061008

出版商:John Wiley&Sons, Ltd    

年代:1956

数据来源: WILEY