摘要:

The effect of HCl on the infrared spectrum of nylon in the form of Zytel films was studied in the region 3600 cm.−1to 600 cm.−1. The effect of partial deuteration of the films was also observed. Definite changes in the characteristic bands of the NH—CO group show that HCl interacts with this group. The results indicate that the two NH bands at 3300 cm.−1and 3030 cm.−1are associated with different NH bonds. The general effect of the HCl seems best explained by assuming a polar interaction with the peptide linkage. The behavior of several of the bands is readily explained on the basis of the picture given by Fraser and Price for the NH—CO vibration.

ISSN:0008-4042    

DOI:10.1139/v57-165

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

not available

ISSN:0008-4042    

DOI:10.1139/v57-166

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Using a reversible silver – silver chloride reference electrode, described in the first paper of this series, standard electrode potentials have been established for the systems lead – lead chloride, zinc – zinc chloride, and nickel – nickelous chloride, in melts containing equimolar quantities of KCl and NaCl. Deviations from ideality were observed, and these were attributed to the formation of complexes. Dissociation constants for the complexes were calculated. The effect of temperature on the electromotive forces of the voltaic cells was also measured, and the heats of the cell reactions were calculated from the data.

ISSN:0008-4042    

DOI:10.1139/v57-167

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Nearly quantitative yields of guanidine have been obtained by heating a mixture of ammonium thiocyanate, sulphur dioxide, and ammonia under moderate pressure. Guanidine is present chiefly as the sulphamate. When a molar ratio of ammonium thiocyanate, sulphur dioxide, and ammonia of 1:3:7 respectively was used, approximately one mole of guanidine sulphamate was produced together with half a mole of ammonium sulphate and more than two moles of elemental sulphur. The reaction products are in the molten state at the synthesis temperature, and with a suitable reactor capable of withstanding corrosion, the reaction has possibilities as a continuous process.

ISSN:0008-4042    

DOI:10.1139/v57-168

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Photo-initiated free radical polymerization of methyl acrylate in aqueous solution is described. Using mainly light of wavelength 3650 Å and the ion pairs Fe3+OH−and Fe3+Cl−as photosensitizers the kinetics of polymerization were investigated by studying the effect of the variation of (i) intensity of light, (ii) concentration of monomer, (iii) fraction of light absorbed by the ion pair, and (iv) ferrous ion accumulating in, or initially added to, the system on (a) molecular weight of polymer, (b) the rate of disappearance of monomer, and (c) the rate of production of ferrous ion. The results have been analyzed in the light of a reaction scheme involving (1) a primary photochemical process and a dark back reaction, (2) initiation of polymerization by the primary product Fe2+OH or Fe2+Cl, (3) dissociation of the primary product, (4) a secondary dark back reaction, (5) initiation by a free radical, (6) propagation, and (7) termination. Examination of the experimental results in the light of the reaction scheme indicated that the initiation of polymerization was due to OH or Cl free radicals formed by the dissociation of the primary product and that termination occurred by combination of growing polymer chains. Some expressions involving specific rate constants have been evaluated.

ISSN:0008-4042    

DOI:10.1139/v57-169

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

A modification of the dithizone colorimetric procedure for determination of lead has been developed. By working in an aqueous acetone system (70% acetone by volume) the usual extraction step is avoided. Aqueous ethanol or methanol may also be employed or, under suitable circumstances, water may be omitted from the solvent system. The 70% acetone system proposed is tolerant of cyanide, added to convert interfering ions into non-interfering complex ions, and the interference of copper under the conditions adopted was determined. This system was also found compatible with hydroxylamine, used as stabilizer, and with the barbital buffer. A reproducibility of about 2% was obtained when working with standards in the range from 0 to 10 μg. of lead and the technique was found to be sensitive to 0.1 p.p.m.

ISSN:0008-4042    

DOI:10.1139/v57-170

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Acetylation of the hydrochlorides of guanidine, cyclohexylguanidine, and 1-guanylpiperidine has been found to yield substituted triazines. Trifluoroacetylation of 1-guanylpiperidine hydrochloride also gives a triazine, whereas guanidine hydrochloride and cyclohexylguanidine hydrochloride are converted tobistrifluoroacetyl derivatives. The same triazines can also be obtained by acylation of the appropriate biguanide.

ISSN:0008-4042    

DOI:10.1139/v57-171

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

An ionization gauge has been modified to serve as a detector for gas chromatography. A small fraction of the effluent gas from the column is diverted into the gauge through an adjustable leak. The gauge is operated under conditions such that ionization of the eluted compound only occurs, and not of the helium carrier. The ion current is amplified and displayed on a pen recorder. The gauge combines very high sensitivity and rapid response with almost complete independence of changes in flow rate, pressure, or temperature.

ISSN:0008-4042    

DOI:10.1139/v57-172

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Hydrogen chloride was apparently destroyed by catalyzing the recombination of nitrogen atoms, the maximum observed rate of destruction being less than one sixth of the active nitrogen flow rate. The effects on the hydrogen chloride – active nitrogen reaction of added chlorine and added hydrogen indicated the reaction between hydrogen atoms and molecular chlorine to be the most important secondary reaction.

ISSN:0008-4042    

DOI:10.1139/v57-173

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

2-Chloronitrobenzene and 2,5-dichloronitrobenzene were reduced with sodium arsenite, dextrose, lactose, maltose, sodium hydroxide and alcohols, and potassium hydroxide and ethanol. The effects of sodium hydroxide, temperature, time, Tergitol, and Lignosol were studied for the arsenite and dextrose reductions. 2-Bromonitrobenzene was also reduced with sodium arsenite and dextrose in alkaline medium. These reductions gave rise to four new phenazine derivatives. 2,4-Dinitrochlorobenzene, when reduced with sodium arsenite, in alkaline medium, yielded only 2,2′-dichloro-5,5′-dinitroazoxybenzene.

ISSN:0008-4042    

DOI:10.1139/v57-174

出版商:NRC Research Press    

年代:1957

数据来源: NRC