摘要:

AbstractAfter a brief review of previous work experiments are described showing the effect of formulation and conditions of production on the stability or shelf life of resortinol‐formaldehyde condensation products. Consideration is given at the same time to the best means of causing the condensation product to set to a strong cement. Examples are given, using an asbestos base laminated plastic, of the shear strength of lap joints from suitably formulated cements. The effect of immersion of these joints in boiling water, dilute acids and alkalis and the effect of exposing them to very dry and very humid atmospheres is describe

ISSN:0368-4075    

DOI:10.1002/jctb.5000661001

出版商:John Wiley&Sons, Ltd    

年代:1947

数据来源: WILEY

摘要:

AbstractA method is described for the volumetric determination of phenol of methylol (CH2OH) groups in phenol alcohols and resins derived therefrom. The method depends on the oxidation and elimination of the methylol group as formic acid by means of iodine. The method has been applied to a series of pure phenol alcohols and to various phenolic resins. It is shown that the accuracy of the method falls (and by the nature of the process must fall) with decreasing methylol content. The range of accuracy is 0·5–3·0% as the methylol content falls from 25–30% to 10%, which is the range commonly encountered. Exceptionally low figures may be met with in e.g., ammonia catalysed phenolic resins, and in such cases the results may be difficult to inte

ISSN:0368-4075    

DOI:10.1002/jctb.5000661002

出版商:John Wiley&Sons, Ltd    

年代:1947

数据来源: WILEY

摘要:

AbstractSimple relations are given for the variation of the latent heat of vaporization of non‐associated liquids with the absolute temperature and the density. These relations are applicable over ranges of 50° and 100°, respectively, above the boiling point of the liquid. It is shown that the latent heat of vaporization of water is inversely proportional to the square‐root of the absolute temperature for the range 100°‐150°. A relation is also given for the variation of density of non‐associated liquids with

ISSN:0368-4075    

DOI:10.1002/jctb.5000661004

出版商:John Wiley&Sons, Ltd    

年代:1947

数据来源: WILEY

摘要:

AbstractThe preparation of guanidinium and substituted guanidinium salts is described. The method consists of boiling, in a suitable solvent, the corresponding alkali metal salt and an inorganic guanidinium salt, e.g., the hydrochloride or sulphate.

ISSN:0368-4075    

DOI:10.1002/jctb.5000661005

出版商:John Wiley&Sons, Ltd    

年代:1947

数据来源: WILEY

摘要:

AbstractA method of acylating long chain primary aliphatic amines is described. Representative series of N‐monoalkylstearamides, N,N′‐dialkyladipamides and N,N′‐dialkylsebacamides, in which each alkyl radical contains between 8 and 18 carbon atoms, have been prepared by acylating the long chain primary amine with the corresponding acid amide. The products are all wax‐like substances. The N,N′‐dialkyladipamides and N,N′‐dialkylsebacamidcs are extremely stable substances; they have relatively high melting points (60°‐145°) and may be used in place of some of the more

ISSN:0368-4075    

DOI:10.1002/jctb.5000661006

出版商:John Wiley&Sons, Ltd    

年代:1947

数据来源: WILEY

摘要:

AbstractFollowing an introduction and a brief review of published work on copper acetylides, investigations into conditions of formation and properties of copper acetylides are described. Parts I and II deal with formation from acid and alkaline, cuprous and cupric solutions. Part III concerns the formation of acetylides on the surfaces of copper and copper alloys under varying conditions. Although acetylides cannot be formed in cupric solutions above a certain acid concentration, they can be formed on the surfaces of copper and brasses immersed in such solutions even if the acidity is greatly increased. Explosive acetylides can be formed not only on copper and high‐copper alloys in ammoniacal acetylene atmospheres, but also on copper and brasses containing 50% copper or more, when these have been contaminated with acids or caustic alkalis. Methods are given for the detection of small amounts of copper acetylid

ISSN:0368-4075    

DOI:10.1002/jctb.5000661007

出版商:John Wiley&Sons, Ltd    

年代:1947

数据来源: WILEY

摘要:

AbstractThe diazoaminogroup (—N=N·NH—) was found to be silver, mercury and cadmium selective. The sulphonamide group (—SO2·NH—) as present in sulphanilamide and other sulpha drugs is similarly reactive. Para diethylaminobenzeneazo chromotropic acid (“chromotropic blue”) was found to be cerium, calcium, magnesium and under certain conditions copper, nickel and cobalt selective. Copper specific and nickel‐selective, is 5‐(p‐nitrobenzeneazo)‐7‐nitroso‐8‐hydroxyquinoline (“oxin violet”). New reactions of nitroso‐R‐acid and photographic reactions of some of th

ISSN:0368-4075    

DOI:10.1002/jctb.5000661008

出版商:John Wiley&Sons, Ltd    

年代:1947

数据来源: WILEY

摘要:

AbstractThe orthosilicates and metaphosphates of cetyltrimethyl‐ammonium bromide (“Cetavlon”)or of “Sapamine KW 200%,” absorb acid dyes and acid spot test reagents and therefore provide analytical “trace catchers.” “Cetavlon” also precipitates mercury, gold and platinum, or, rather, their anionic complexes (chloro‐aurates and platinates) from slightly acid or neutral solutions of the metal chlorides. Spot test papers with sapamine iodide are very selective for platinum and palladium and more sensitive than those with 2‐thiolbenziminazole. The oxidation of aromatic amines is greatly influenced by a

ISSN:0368-4075    

DOI:10.1002/jctb.5000661009

出版商:John Wiley&Sons, Ltd    

年代:1947

数据来源: WILEY

摘要:

AbstractA review of the literature is followed by an account of work in which the soil to be examined is left for a period in contact with a solution of malachite green dye which is examined photo‐electrically before and after contact. Reference is made to the work of Hogentogler and others on the subject but the methods now described are radically different especially with regard to contact times. Soil dye adsorptive capacities are reported for 32 soils ranging from an almost pure sand to an almost pure clay and the effect of surface area on adsorption is also discussed, it being shown that the total adsorption of a fraction of a soil is dependent upon : (a) the clay‐type present and its physico‐chemical nature, and (b) the surface area of the constituent grains in the fra

ISSN:0368-4075    

DOI:10.1002/jctb.5000661010

出版商:John Wiley&Sons, Ltd    

年代:1947

数据来源: WILEY

摘要:

AbstractSubstantial quantities of DL‐methionine were urgently required by the Medical Research Council in England during the latter part of the war. The Ministry of Supply undertook the development up to a pilot scale of a process thought to be suitable for quantity production of methionine of high purity. The results of the first stages of this development, i.e., laboratory research, have already been published.1The present paper is concerned with the semi‐technical and pilot scale development of the proc

ISSN:0368-4075    

DOI:10.1002/jctb.5000661011

出版商:John Wiley&Sons, Ltd    

年代:1947

数据来源: WILEY