摘要:

The radiolysis of cyclohexane has been studied at low total doses and initialGvalues have been determined. Ninety-nine per cent of the evolved hydrogen has been accounted for in hydrogen-deficient products. Cyclohexene, bicyclohexyl, and cyclohexyl-hexene-1 have been identified as primary reaction products. Cyclohexyl-cyclohexene has been identified as a secondary reaction product. The use of high irradiation doses has been shown to lead to decreases in the initialGvalues of all primary products.

ISSN:0008-4042    

DOI:10.1139/v61-316

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

A method for separating small amounts of rhodium from iridium is described. In 3 to 9 Mhydrochloric acid solutions, the amber-to-red complex of bivalent rhodium with 4,5-dimethyl-2-mercaptothiazole is formed after reduction of tervalent rhodium with chromous or stannous chloride. Rhodium is quantitatively separated from iridium by chloroform extraction of this product; separation can be made in solutions that have been fumed with sulphuric acid if chromous chloride is used for the prior reduction of the rhodium. The complex, after removal of the chloroform, is dissolved in dilute hydrochloric acid, and the optical density of the resulting colored solution is measured.

ISSN:0008-4042    

DOI:10.1139/v61-317

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

Samples of oriented nylon film and filament were treated with anhydrous HCl and examined in the near-infrared region of 9000 to 3700 cm−1with polarized light. The results are in agreement with previous observations made in the 3600–600 cm−1region, and corroborate earlier evidence that HCl interacts with the peptide linkage. The disorienting effect of the HCl is also reflected in the spectrum of the treated specimens.

ISSN:0008-4042    

DOI:10.1139/v61-318

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

The microbiological oxidation of 1-deoxy-1-N-methylacetamido-D-glucitol and 2-acetamido-1,2-dideoxy-D-glucitol yielded a syrupy ketose and a crystalline ketose respectively. Crystalline derivatives of each were prepared and structural investigations of the ketoses showed the former to be 6-deoxy-6-N-methylacetamido-L-xylohexulose and the latter to be 5-acetamido-5,6-dideoxy-L-xylohexulose.

ISSN:0008-4042    

DOI:10.1139/v61-319

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

It was shown previously that, when an inert gas is irradiated with neutrons in the presence of a powdered solid, between 0.1 and 14% of the induced inert-gas activity is firmly "attached" to the solid. The manner in which attached inert-gas activity is released at temperatures between 50 and 800 °C has now been studied. Release data were assembled for a number of systems, and it was noted that the release was reproducible and apparently a diffusion phenomenon. Several theoretical treatments based on diffusion theory were then explored. Agreement between theory and observation was poor if a constant activation enthalpy was assumed. Agreement was good, on the other hand, with theory that took account of the damaged condition of the solid, and the existence of composition anomalies, in the surface region where the inert-gas activity was attached. The damage and composition anomalies were assumed to lead to a spectrum of activation enthalpies and thence to a simplified diffusive motion involving a single rate-controlling jump. The activation-enthalpy spectra for the systems Ar–Nb and Xe–Nb were found to be identical, extending from about 25 to 47 kcal. The spectrum for Xe–Nb2O5extended from about 28 to 76 kcal, and was, in general, similar to the spectra for Xe–SiO2, Ar–TiO2, and Xe–TiO2.

ISSN:0008-4042    

DOI:10.1139/v61-320

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

A glucomannan containingD-mannose andD-glucose in a molar ratio of 7:3 has been isolated from sugar maple sapwood. Electrophorectic examination in acetate and borate buffers showed that the polysaccharide was essentially homogeneous. Methylation and hydrolysis of the glucomannan yielded the followingO-methyl ethers:2,3,4,6-tetra-O-methyl-D-glucose (1.1%),2,3,4,6-tetra-O-methyl-D-mannose (2.3%),2,3,6-tri-O-methyl-D-glucose (23.4%),2,3,6-tri-O-methyl-D-mannose (65.9%),2,3-di-O-methyl-D-glucose (2.6%),2,3-di-O-methyl-D-mannose (2.7%).These data in conjunction with periodate oxidation results and estimates of the degree of polymerization indicated that the glucomannan was composed of 25–27 hexose units linked β(1 → 4) in a linear structure. The chains were terminated predominately byD-mannose units; traces ofD-xylose were present in terminal positions only and appeared to be part of the glucomannan molecule.

ISSN:0008-4042    

DOI:10.1139/v61-321

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

Two compounds, originally formulated by Price as Na2Mn2I2O11and K2Mn2I2O11have been shown to be NaMnIO6•1/2H2O and KMnIO6•1/2H2O. Consequently they are compounds of tetravalent manganese, a conclusion confirmed by their magnetic susceptibilities, and by their reactions with a variety of reducing agents; the reactions with ferrous ions, iodide ions, sulphur dioxide, hydroxylamine hydrochloride, and hydrazine hydrochloride were examined. Some of the properties of these compounds are described, and their X-ray powder diagrams show them to be analogous to the nickel salts NaNiIO6•H2O and KNiIO6•1/2H2O.

ISSN:0008-4042    

DOI:10.1139/v61-322

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

The reaction of benzene with oxygen atoms produced by mercury photosensitized decomposition of nitrous oxide has been studied in a circulating system at room temperature. The main reaction product is a non-volatile material probably largely aldehydic in character. This is tentatively assumed to result from the rearrangement and polymerization of the initially formed adduct. Smaller amounts of phenol and carbon monoxide are also formed. The rate of formation of carbon monoxide decreases with increasing pressure, suggesting an energy-rich precursor.Oxygen atoms react with benzene much more slowly than with olefines. At 120° cyclopentene reacts about 150 times more quickly than benzene. The activation energy of the reaction of oxygen atoms with benzene has been estimated at 4.6 to 4.9 kcal/mole, with an uncertainty of about 0.7 kcal/mole.

ISSN:0008-4042    

DOI:10.1139/v61-323

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

The reaction of toluene with oxygen atoms produced by mercury photosensitized decomposition of nitrous oxide has been studied at room temperature. The reaction shows a general similarity to the corresponding reaction of benzene. Relative rates have been determined at 120 and 220 °C and the activation energy estimated at close to 4 kcal/mole.

ISSN:0008-4042    

DOI:10.1139/v61-324

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

The ultraviolet absorption spectra and infrared carbonyl bands of a number of substituted benzoyl chlorides are determined. It is found that as a first approximation theB-bands of the ultraviolet spectra are similar for benzoyl chlorides and for the corresponding benzaldehydes and acetophenones. The spectra are discussed in terms of previously stated hypotheses. In this way the order of the apparent negative mesomeric effect is deduced to be —NO2 > — COCl > —CHO > —COCH3, and the effective size of these substituents is confirmed to be in the order —NO2 > —COCH3 > —COCl > —CHO.The infrared carbonyl band occurs as a well-defined doublet in most of the ring-substituted benzoyl chlorides. The most probable explanation is that these doublets occur because of an intramolecular vibration.

ISSN:0008-4042    

DOI:10.1139/v61-325

出版商:NRC Research Press    

年代:1961

数据来源: NRC