摘要:

A procedure for preparing magnesium carbide, Mg2C3; in 300 gm. lots is described. Propyne-d4was prepared in good yields by the action of deuterium oxide on this carbide. The acetylenic deuterium in propyne-d4was replaced by hydrogen via the mercury derivative giving propyne-3-d3The vapor pressures of propyne-3-d3,and propyne-d4were determined between −25 °C. and −60 °C.

ISSN:0008-4042    

DOI:10.1139/v52-012

出版商:NRC Research Press    

年代:1952

数据来源: NRC

摘要:

Dielectric dispersion in solid polyvinyl butyral was investigated at frequencies of 0.3, 1, 3, 10, 30, and 100 kc. at temperatures from 20° to 140 °C. The data indicated severely restricted dipole rotation and yielded an extrapolated relaxation time of 104  sec. at 25 °C. The application of the theory of absolute reaction rates yielded an enthalpy of dielectric relaxation of 65.2 kcal. and a constant entropy of 139 e.u. These values furnish a basis for a quantitative measure of dipole hindrance and were compared with data available for other polymers.

ISSN:0008-4042    

DOI:10.1139/v52-013

出版商:NRC Research Press    

年代:1952

数据来源: NRC

摘要:

Rhombifoline is isomeric with thermopsine and anagyrine, and, like both these alkaloids, contains an α-pyridone ring. It can be dealkylated to cytisine, and, on catalytic hydrogenation, yields octahydrodesoxyrhombifoline, which is identical with hexahydrodesoxy-N-(n-butyl)-cytisine, the hydrogenation product of N-(n-butyl)-cytisine. The results of the hydrogenation thus indicate that the molecule of rhombifoline contains a third double bond, which is shown by its infrared spectrum to be located at a terminal methylene group. Rhombifoline is therefore N-(but-3-enyl)-cytisine, a conclusion which was confirmed by the partial synthesis of the alkaloid from cytisine.

ISSN:0008-4042    

DOI:10.1139/v52-014

出版商:NRC Research Press    

年代:1952

数据来源: NRC

摘要:

By means of chloride-catalyzed nitration, polynitroamines analogues of Edna (N,N′-dinitroethylenediamine) were prepared in fairly good yields. The compounds to be nitrated were obtained by the condensation of acetonecyanohydrin with ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine. The secondary amines resulting from the condensation, although less basic in character, have nevertheless required for nitration the addition of one equivalent of chloride catalyst. When the products of the condensation with acetonecyanohydrin were isolated, as hydrochloride salts, no additional chloride was needed to assure nitration. The analysis of the hydrochloride derivatives were found to be in close agreement with the proposed structural formula.

ISSN:0008-4042    

DOI:10.1139/v52-015

出版商:NRC Research Press    

年代:1952

数据来源: NRC

摘要:

The rate of polymerization increased with purification of the monomers. It was possible that the dienes formed cyclic compounds or dimers in side reactions. The 1,2 addition of the monomer decreased with decreasing polymerization temperature. A study was made of the copolymerization of isoprene and dimethylbutadiene with styrene at −18° C. From analyses of bound diene in the product at various conversions and initial diene to styrene ratios the reactivity ratios for these diene-styrene systems were calculated to ber1 = 1.30 ± 0.02 andr2 = 0.48 ± 0.01 for isoprene and styrene andr1 = 0.92 ± 0.02,r2 = 0.42 ± 0.02 for dimethylbutadiene and styrene (styrene always being considered monomer 2).Qandevalues from the Alfrey-Price equation were calculated asQ = 119 ande = −0.112 for isoprene andQ = 1.09 ande = −0.181 for dimethylbutadiene relative toQ = 1.0 ande = −0.8 for styrene. Fom these and the values previously determined for butadiene, reactivity ratios for all combinations of the three dienes were calculated. The chain transfer reaction between dienyl radicals and mixed tertiary mercaptans was studied and it was found that isoprenyl and dimethylbutadienyl radicals were much more reactive than butadienyl. The effect of this was illustrated by number and viscosity average molecular weights. Intrinsic viscosities of homo- and copolymers formed in a mercaptan-free recipe were measured and compared.

ISSN:0008-4042    

DOI:10.1139/v52-016

出版商:NRC Research Press    

年代:1952

数据来源: NRC

摘要:

Tetramethylolcyclopentanone was hydrogenated (70% purified yield) and nitrated (74% purified yield) to give 2,2,5,5-tetramethylolcyclopentanol pentanitrate, m.p. 91°, a powerful explosive only slightly weaker than RDX. A number of its properties were determined.

ISSN:0008-4042    

DOI:10.1139/v52-017

出版商:NRC Research Press    

年代:1952

数据来源: NRC

摘要:

Measurements of conductance and fluidity of silver nitrate and of ammonium nitrate solutions, over a range of concentration varying from 0.05  Nto 14 N(silver nitrate) and from 0.08  Nto 15  N(ammonium nitrate) have been made. In both cases, a maximum is observed in the specific conductances but in neither case does a minimum occur in the plot of equivalent conductance against concentration. While the equivalent conductance in very dilute solutions is proportional to, in very concentrated solutions it appears to be directly proportional toC. Temperature coefficients of conductance and of fluidity are evaluated and their theoretical importance discussed. Partial molar volumes of water in these solutions are evaluated.

ISSN:0008-4042    

DOI:10.1139/v52-018

出版商:NRC Research Press    

年代:1952

数据来源: NRC

摘要:

A study has been made of the nitrogen isotope effects occurring in the deammonation of phthalamide of normal isotopic abundance. It has been found that the reaction of phthalamide-N14N15leading to N14H3formation occurs 1.2% more readily than that giving N15H3. In addition, a 0.6% greater probability of formation of N14H3from phthalamide-N14,N15than from phthalamide-N14,N14has been observed, due consideration being given to the presence of one N14atom in the former and two N14atoms in the latter amide species. An explanation has been advanced based on the effect upon activation energy of the isotopic mass of the nitrogen atom in the C–N bonds broken and formed in the reaction.

ISSN:0008-4042    

DOI:10.1139/v52-019

出版商:NRC Research Press    

年代:1952

数据来源: NRC

摘要:

A method is described for the precise measurement of the activity coefficients of salts in mixed electrolytic solutions. It involves the use of synthetic ion exchange resins and radioactive tracers. The activity coefficients of the chlorides of sodium, potassium, rubidium, and cesium were measured at effectively zero concentration in hydrochloric acid solutions from 0.005 to 1.5 m. The activity coefficient of sodium chloride in solutions of lithium and potassium chlorides was also determined. The results are discussed in terms of both the Harned rule and the Stokes–Robinson theory of activity coefficients.

ISSN:0008-4042    

DOI:10.1139/v52-020

出版商:NRC Research Press    

年代:1952

数据来源: NRC

摘要:

not available

ISSN:0008-4042    

DOI:10.1139/v52-021

出版商:NRC Research Press    

年代:1952

数据来源: NRC