摘要:

Bromal labelled with C14in the carbonyl group has been used to show that small amounts of carbon dioxide and carboxylic acids are produced in the radiolysis of aqueous bromal solutions.Gvalues for the production of CO2and carboxylic acid are about 7.5% and 15% of those for HBr production, respectively. The observed yield of carboxylic acid is in agreement with that found by titration.

ISSN:0008-4042    

DOI:10.1139/v59-167

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

The electric dipole moments of six possible rotamers comprising the two diastereomeric forms of 2,5-dimethyl-2,5-dimethoxy-3,4-diphenylhexane have been calculated vectorially. Comparison of these values with the experimental determination of polarization in benzene and carbon tetrachloride shows that only two of the rotamers of thedd,llform and only one of themesoform are present in significant amount. The moment of thedd,lldiastereomer decreases with increasing temperature but that of themesoform is almost invariant. It is probable that all six central linkages in these diastereomers are hindered from free rotation.

ISSN:0008-4042    

DOI:10.1139/v59-168

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

The infrared spectra of a number of malonates and oxalates (as liquid films) were examined at various temperatures and narrower slit widths than had previously been used. The absorption in the 5.8 μ region is very complex, at least four bands being observed in each case. Small but definite temperature effects were recorded for both types of esters. At somewhat wider slit widths only two bands were observed, these occasionally having indistinct shoulders. The spectra of some of the compounds were also measured in both carbon tetrachloride and acetonitrile solutions (two bands observed in each case) and the ratios of the intensities of the two bands compared. A possible explanation of the effects observed is that at least two rotational isomers can exist for each compound and that vibrational coupling of the carbonyl stretching frequencies can occur in each of the rotational isomers.

ISSN:0008-4042    

DOI:10.1139/v59-169

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

Stream-current, permeability, and conductance measurements were made on cylindrical pads of randomly oriented Dacron, glass, Nylon, and Orlon fibers over a range of electrolyte and solid concentrations. Values of the specific surface conductivity were computed from the conductance data, using equations which were derived from a capillary network theory.The measured conductance values were independent of pad concentration, increased with increasing electrolyte concentration, and were higher than values calculated from electrical double-layer theory using the measured values of ζ-potential. A number of plausible reasons for the discrepancies are advanced.

ISSN:0008-4042    

DOI:10.1139/v59-170

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

Evidence is presented that the ketenimine intermediate formed in the thermal decomposition of azo-bis-isobutyronitrile (AIBN) rearranges quantitatively to tetramethylsuccinodinitrile (TMSDN), mainly by a molecular mechanism. Interpretation of experimental data on the basis of a reaction scheme consistent with the nature of the main products and the features of the kinetics of the decomposition permits estimation, by means of a simple diagram, of the extent of disproportionation, as well as that of the normal and abnormal recombination of cyanisopropyl radicals. The result obtained for the latter is in good agreement with that determined previously by an alternative method. The analysis does not exclude absolutely the possibility of side reactions in which the azo-compound partly decomposes by a molecular process, and the intermediate decomposes into free radicals. However, it is concluded that these side reactions, if any, must be of minor importance.

ISSN:0008-4042    

DOI:10.1139/v59-171

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

The binary system Na3AlF6–Na2SO4has been investigated. A eutectic point was found at 91 mole % Na2SO4. On the Na3AlF6side of the diagram extensive solid solution was found. No solid solution was observed on the Na2SO4side, either by thermal analysis or by Debye–Scherrer diagrams. The freezing point depression of Na2SO4caused by additions of Na3AlF6has been used to evaluate the dissociation scheme of the cryolite anion in a sodium sulphate melt. The calculations favor the following scheme:AlF63− = AlF4− + 2F−.

ISSN:0008-4042    

DOI:10.1139/v59-172

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

The over-all stoichiometry of the reactions involving titanium tetrachloride and various organometallic compounds has been determined. While titanium tetrachloride reacts with aluminum ethyldichloride and lead tetraethyl according to a 1:1 stoichiometry for any ratio investigated, the reaction between aluminum triethyl and titanium tetrachloride proceeds according to different paths when the ratio of the reagents is changed. Equations describing the reactions between aluminum triethyl and titanium tetrachloride, where the stoichiometries are respectively 1:1, 1:2, 1:3, are derived. Although a certain amount of hydrogen has been isolated after hydrolysis of the products of these reactions, no definite evidence is found for the presence of Ti(II).In all the experiments (except those in which an Al/Ti ratio greater than unity was used) substantial amounts of ethyl chloride and ethylene have been found, together with the main gaseous components, ethane and butane. A higher alkane was also isolated from the solid products of the reaction and is equal to the quantity of ethane liberated.

ISSN:0008-4042    

DOI:10.1139/v59-173

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

Royline and inuline, previously isolated fromInularoyleana, have again been isolated from this source, and shown to be lycoctonine and anthranoyl-lycoctonine respectively. The presence of a third known alkaloid, methyl-lycaconitine has also been established. This is the first recorded occurrence of lycoctonine and its derivatives outside the family Ranunculaceae.

ISSN:0008-4042    

DOI:10.1139/v59-174

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

Difficulties of determining the binding energies and effective charges on the atoms are the main reason why no systematic explanation of the variation of the size of the energy gap among members of the simplest family of semiconductors—those with the zinc blende structure—has ever been given. It is shown that by the choice of suitable atomic parameters for discussing the activation energies of these compounds these difficulties may be avoided, and the variation of the size of the energy gap between one compound and another can be systematically accounted for. In the treatment which develops no particular distinction need be made between the III–V, II–VI, and I–VII compounds, and it is concluded that the anomalously high or low activation energies, which certain compounds appear to have, are just the result of the relative sizes of the cations and anions in influencing the polarization of the bonds.

ISSN:0008-4042    

DOI:10.1139/v59-175

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

When methionine-Me-14C, pyridoxine, and folic acid were fed to growing alfalfa, the stachydrine isolated from the plant was radioactive. This observation supports the assumption that stachydrine arises from proline by methylation since pyridoxine has been shown to induce the formation of proline from ornithine in the plant. However, the administration of labelled ornithine, pyridoxine, folic acid, and methionine to alfalfa failed to produce the radioactive alkaloid. Similar experiments were performed in which methionine-Me-14C and folic acid, methionine-Me-14C and pyridoxine, and finally methionine-Me-14C alone were fed to alfalfa, and in each case the stachydrine isolated from the plant was radioactive, while the homostachydrine remained inactive. Feeding proline-carboxyl-14C to alfalfa failed to produce radioactive stachydrine. It must be concluded that in alfalfa which is 2 to 3 weeks old, stachydrine is actively synthesized although homostachydrine is not. The implications of these observations are discussed.

ISSN:0008-4042    

DOI:10.1139/v59-176

出版商:NRC Research Press    

年代:1959

数据来源: NRC