摘要:

AbstractThis paper describes the construction and operation of a straightforward photo‐electric absorptiometer of original design. The instrument may be readily constructed in the laboratory workshop from standard parts, and is suitable for most routine colorimetric determinations at present carried out with more complicated and expensive apparatus. Tests in these laboratories have shown that the instrument is sufficiently robust and stable to withstand continued use under routine conditions and that the accuracy of reading and stability of calibration are both well up to the standard set by more expensive instruments. The preliminary design was drawn up on the following broad principles, which were considered to be the characteristics of an ideal ubsorptiometer : (1) Robust and simple construction. (2) Freedom from personal errors. (3) Good reproducibility of readings. (4) Permanency of calibration, (5) Rapid reading. (6) Liquid cell easy to, fill and drain, preferably without removal from the instrumen

ISSN:0368-4075    

DOI:10.1002/jctb.5000650401

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractWhen tinplate in immersed for 20 sec. At 85° in an alkaline phosphate‐eliminate solution containing n penetrating agent it acquires an invisible film which protects it against blackening by sulphur‐containing foods, and also greatly retards rusting in moist air. An account is given of cannery trials in which the protective film was applied to tinplate cans after filling by adapting the can‐washing machinery, and of a large‐scale experiment in which tinplate sheets were treated by the same process before fabrication into cans, Cans manufactured from treated tinplate combine the advantages of freedom from internal blackening and increased resistance to external rusting, and for a number of packs the amount of tin absorbed by the food during storage is less than in cans made from untreated

ISSN:0368-4075    

DOI:10.1002/jctb.5000650402

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractConsideration is given to the precautious which must he adopted in standardising the conditions for the examination of cultures ofAectobacterspecies in order that comparisons may be obtained for diagnostic purposes. The media and the technique which were employed for thin purpose are then deseribed. Particulars are also given of ten species ofAcctobacterwhich were examined under the standardised conditions adopted. The results of this examination will form the subject of part II.

ISSN:0368-4075    

DOI:10.1002/jctb.5000650403

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractThe benzoyl peroxide catalysed polymerisation of diallyl phthalate is shown to proceed by a zero order reaction in the early stages to give a linear or lightly branched unsaturated polymer (β‐polymer). At approximately 25% conversion, gel formation occurs duo to the formation of a three‐dimensional polymer (γ‐polymer). Thereafter the β‐polymer concentration falls rapidly as the γ‐polymer content increases.The polymerisation of mixtures of unsaturated polyesters, typified by diethylene maleste, and diallyl phthalate is shown to result mainly in a three‐dimensional copolymer.The effect of temperature variation on multi‐functional polymerisation reactions of the above type is discussed. It is suggested that, as the polymerisation temperature is increased, fewer cross‐links by primary valence bonds are formed, i.e., Houwink's “Lockerstellen” theory may be extended to includ

ISSN:0368-4075    

DOI:10.1002/jctb.5000650404

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractThe contamination of sea water magnesia by calcium sulphate has been investigated, and is shown to be due to the decreasing solubility of the Bait in the spent sea water as magnesium is progressively replaced by calcium. The saturation point has been determined by dissolving calcium sulphate dihydrate in samples of treated sea water of varying magnesium content, and has been found to occur at a calcium ion concentration of 96·0 mgm. equivalents per 1.000 gm. when 72·5% of the total magnesium has been precipitated as magnesium hydroxid

ISSN:0368-4075    

DOI:10.1002/jctb.5000650405

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractThe chemical coustitution and crystalline structure of clay particles and the physical structure of clay particles and clay suspensions are discussed in relation to the behaviour of sub‐grades and foundations in road constructio

ISSN:0368-4075    

DOI:10.1002/jctb.5000650406

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractThe seeds of this sub‐family have a very low content fixed oils, which are highly coloured and contain a high proportion of msaponifiable matter. In moat canon the mixed fatty acids contain about 30% of suturated acids, the balance being a mixture of oleic and linoleie acids, the amounts of the two hitter varying with the species. In all cases, fatty acids of high molecular weight were shown to lie present, a fact that appears to be a characteristic of the entire Legmninoste famil

ISSN:0368-4075    

DOI:10.1002/jctb.5000650407

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractA method for the determination of tar fog in gas is described. Tests made on the removal of tar fog from carburetted water gas in multi‐stage high‐speed exhauster are described and the importance of good cooling of the gas pointed out. Tests made on a coal gas stream containing high‐speed exhausters show that provided there is good cooling in the secondary condensers the tar fog entering the purifiers can be reduced to a very low f

ISSN:0368-4075    

DOI:10.1002/jctb.5000650408

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractThe salicylaldehyde reaction fur the detection of acetone has been studied. It has been shown that the range of specificity hitherto suggested is much too narrow and that the mechanism of the reaction postulated by Braunstein is untenable. A positive salieylaldehyde reaction is given by a wide variety of substances, the essential conditions being condensation of the salieylaldehyde with a reactive methylene group and the formation, through the phenolic hydroxyl group in the salicylaldehyde molecule, of the sodium Bait of the resulting compound. With a relatively concentrated solution of acetone, at any rate, the red colour is due to the formation of the sodium Halt of salieylacetone. Such salts have been isolated and characterised. The reaction is more sensitive for acetone than for any of the other substances examined.

ISSN:0368-4075    

DOI:10.1002/jctb.5000650409

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractThe bromination ofp‐nitrotoluene in the presence of antimony tribromide givesp‐nitrobenzyl bromide, the use of ferric bromide as catalyst results in the formation of 2 bromo as nitrotoluene. The former method is suggested as a convenient one for the preparation ofp‐nitrobenzyl br

ISSN:0368-4075    

DOI:10.1002/jctb.5000650410

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY