摘要:

AbstractThe cross‐linking action of formaldehyde on the arachin and conarachin‐II fractions of groundnut protein in the pH range 6–11 has been studied by means of the ultracentrifuge. When suitable steric conditions obtain, cross‐linking of conarachin II takes place with the formation of dimers, trimers and tetramers of the parent molecule, the optimum effect being obtained at pH 8. In the case of arachin, evidence for the formation of formaldehyde cross‐linkages is found in the effect of the formaldehyde treatment on the dissociation and denaturation reactions of the protein. The nature of the functional groups responsible for the formation of formaldehyde cross‐linkages i

ISSN:0021-8871    

DOI:10.1002/jctb.5010080501

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractA procedure is described for the identification and semi‐quantitative estimation of plasticizers in the mixtures commonly used in the formulation of plastics, especially polyvinyl chloride. It involves chromatographic separation followed by infra‐red spectrosc

ISSN:0021-8871    

DOI:10.1002/jctb.5010080502

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractPotassium permanganate in acetone is shown to be a useful reagent for the oxidation of perfluoro‐and chlorofluoro‐olefins to the corresponding carboxylic ac

ISSN:0021-8871    

DOI:10.1002/jctb.5010080503

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractSilicon nitride has been prepared by heating pure silicon in purified nitrogen at 1450°.X‐ray studies showed the presence of two nitrides, and a method was therefore devised to separate them. Although these nitrides differ in their crystal structure, they have the same compositions, corresponding to Si3N4. A few chemical tests were performed on finely divided silicon nitride prepared at or above 145°. Several alloys containing various proportions of silicon were nitrided under different conditions, and theX‐ray diffraction patterns of the nitrides extracted from these alloys were found to be in complete agreement with that of α‐Si3N4. The diffraction lines obtained from the nitrided alloy prior to any chemical treatment gave nitride lines which did not correspond to those of the α‐Si3N

ISSN:0021-8871    

DOI:10.1002/jctb.5010080504

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractThe evolution of gas from duralumin corroding in an aqueous solution containing 10 g. of HCl + 30 g. of NaCl per litre of solution was studied. To obtain reproducible gas‐evolutions it was found necessary to control specimen surface pre‐treatment and the temperature and composition of the corrosion solution. Duralumin which corroded by pitting evolved gas at an approximately constant rate after an induction period of several hours. The same duralumin, heat‐treated so that it was susceptible to intergranular attack, evolved gas at a rate increasing linearly with time of immersion, after a short induction p

ISSN:0021-8871    

DOI:10.1002/jctb.5010080505

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractA direct titration method for the determination of chlorine in organic compounds containing nitrogen and sulphur is described. The method is applied after wet combustion, the ultimate product, silver chloride, being treated with an ion‐exchange resin, and the liberated hydrochloric acid titrated with standard mercuric nitrate using diphenylcarbazone. A conductimetric finish is also describe

ISSN:0021-8871    

DOI:10.1002/jctb.5010080506

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractAn instrument for the estimation of intensity of odour is described. The dilution required to make the odour just detectable in a mixture with odour‐free air is taken as a measure of the intensity, and the instrument is essentially a mechanical device for making the requisite dilution conveniently.Different persons show markedly different sensitivities to a given odour, and these differences vary widely with different odours. These differences in sensitivity cannot then be estimated from the results obtained with a particular ‘reference’ odour, but must be established from long‐term averages for the material concerned.Day‐to‐day variations in personal sensitivity, and other errors, were small compared with the residual error. Different persons exhibited widely different degrees of reliability in their results, and hence careful selection and training of those using these instruments i

ISSN:0021-8871    

DOI:10.1002/jctb.5010080507

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractLithium deuteride has been prepared by the direct combination of lithium and deuterium at 700°, the deuterium having been obtained from the oxide by the use of magnesium. The isotopic and chemical purity of the product have been determined. Lithium aluminium deuteride has been prepared from lithium deuteride and aluminium bromide

ISSN:0021-8871    

DOI:10.1002/jctb.5010080508

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractA study of both a wetted‐disc and a wetted‐wall column has indicated that the latter is the more suitable for obtaining mass‐transfer data in spite of the tendency to ripple formation.A study has been made of the absorption of hydrogen sulphide and carbon dioxide from a gas mixture with a CO2H2S ratio of 30: 1 in solutions of sodium and potassium carbonates.Selectivity for the absorption of hydrogen sulphide has been found to decrease with increase in wetting rate and with increase in temperature. It increases with increase in gas rate and increases slightly with increase in concentration of sodium carbonate in the solution above about 1·1–1·3‐N. The concentration of hydrogen sulphide in the gas has no effect on the selectivity provided it is more than 1·3% but below this concentration, the selectivity decreases as the concentration decreases.The gas film conditions are more important than those in the liquid film for hydrogen sulphide concentrations in the gas of about 1%. The absorption of carbon dioxide is independent of gas film conditions and is controlled by the rate of a slow reaction in the liquid film.The practical absorption conditions required to secure maximum removal of hydrogen sulphide and minimum removal of carbon dioxid

ISSN:0021-8871    

DOI:10.1002/jctb.5010080509

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY

摘要:

AbstractIn a stationary sound wave over a St. Clair generator emitting about 0·05 w/cm.2at 13·5 kc/s, the decomposition rate of formic acid on a heated nickel filament increased by about 50%, that of ammonia by about 15%, while ethylene hydrogenation was unaffected. The increased rate ran parallel with increased heat‐transfer from the wire when sound intensity or the position of the filament in the sound field was varied; it is attributed to increased mass‐transfer. Both formic acid and ammonia results are consistent with zero order in reactant and inhibition by‐p

ISSN:0021-8871    

DOI:10.1002/jctb.5010080510

出版商:John Wiley&Sons, Ltd    

年代:1958

数据来源: WILEY