摘要:

The infrared spectrum of gaseous CF3NO has been studied in the region 4000–35 cm−1. The infrared spectrum of the condensed phase has also been recorded and a complete vibrational assignment is proposed. Attempts to record the Raman spectrum have been hampered by photolysis. A frequency of 50 cm−1for the CF3torsional mode has been estimated from combination and hot bands. This corresponds to a barrier to internal rotation of approximately 425 cal/mol (150 cm−1). A normal coordinate analysis has been carried out and potential energy distributions, and valence and symmetry force constants are reported.

ISSN:0008-4042    

DOI:10.1139/v74-462

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

The thermal decomposition of β-trifluoroethylsilanes (CF3CH2SiFx(CH3)3−xwherex = 0–3) is described by the reactionThe Arrhenius parameters for the series of silanes studied are as follows:Some results for the decomposition of the hot molecule CF3CH2SiF3* are reported.

ISSN:0008-4042    

DOI:10.1139/v74-463

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

The kinetics of electroreduction of Cr3+ion have been studied at a mercury electrode both in the absence and in the presence of chemisorbed toluenep-sulfonate ions. The rate of the reaction was considerably accelerated in the presence of the chemisorbed anions. Analysis of the data has shown that the reaction acceleration can be accounted for on the basis of Frumkin's theory for double layer effects suggesting that the reaction site is at the outer Helmholtz plane or close to it in the diffuse layer.

ISSN:0008-4042    

DOI:10.1139/v74-464

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

The influence of molecular weight (900 to 1.8 × 106) on the glass transition temperature of low polydispersity polystyrene (anionically prepared) has been studied by differential scanning calorimetry at heating rates of 5 to 80 °C min−1. Over the range of molecular_weight studied, and at an extrapolated heating rate of 1 °C min−1,A thermally prepared polystyrene sample (andPd = 3.2) showed aTgevalue of 93 °C, some 10° below the value predicted by the above equation. Low molecular weight species in the highly polydisperse sample are believed to be responsible for the discrepancy. The changes in heat capacity brought about by the glass transitions are accompanied in all cases on heating by an endothermic peak and this regardless of the heating rate (even extrapolated to 1 °C min−1) or the molecular weight of the sample, suggesting that the glass transition phenomenon encountered with polystyrene is a process involving a positive heat effect.

ISSN:0008-4042    

DOI:10.1139/v74-465

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

Measurements of ϵ′ and ϵ″ at 5 kHz are reported for the system aniline–cyclohexane in the region of the consolute temperature. No anomalously large values of ϵ′ and ϵ″were found in the region of concentration where the binodal curve is essentially flat. Traces of water increase the temperature for phase separation. An explanation in terms of the formation of molecular clusters is offered for the difference of behavior of this system and that of nitrobenzene – trimethyl pentane.

ISSN:0008-4042    

DOI:10.1139/v74-466

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

The effect of pressure on the solubility of CaCO3(calcite), CaF2, and SrSO4in water was investigated for temperatures between 0 and 35 °C for pressures up to 1000 atm. It was found that for SrSO4at 0 °C, and at 22 °C above 500 atm, and CaCO3the high pressure solubility products were appreciably lower than those expected from calculations based on the anhydrous salts. It is postulated that this effect may be due to the formation of a bulk or surface hydrate. Consequently, care must be taken in assigning the solid phase when predicting the pressure dependence of the solubility of a sparingly soluble salt.

ISSN:0008-4042    

DOI:10.1139/v74-467

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

Crystalline sodium tin paraperiodate has been prepared; the X-ray powder diffraction data are indexed to the hexagonal system.The thermal analyses, TG and DTA of MSnIO6, where M = NH4, Na, K, Rb, Cs, reveal that the initial mode of decomposition is via partial evolution of I2and O2.The infrared spectra of these compounds exhibit six well-defined absorption bands. These bands are located within the frequency region characteristic of I—O vibrational modes suggesting a lowering of the normalOhsymmetry for the [IO6]5−species.The electrical conductivity υs. temperature behavior for CsSnIO6is reported

ISSN:0008-4042    

DOI:10.1139/v74-468

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

X-Ray, n.m.r., and dielectric studies show that the hydrate of isoxazole is a typical type II clathrate hydrate in structure, in reorientation rates of host and guest molecules, and in composition.

ISSN:0008-4042    

DOI:10.1139/v74-469

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

Carbon-13 n.m.r. chemical shifts are reported for diphenylmethane and nine methylated derivatives. Results are compared with those for related methylbenzenes. In the case of tri-ortho-substituted materials the predominance of a perpendicular conformation is suggested. Ring current calculations show that in contrast to the1H chemical shift interpretations, the13C shielding trends cannot originate primarily from anisotropic effects.

ISSN:0008-4042    

DOI:10.1139/v74-470

出版商:NRC Research Press    

年代:1974

数据来源: NRC

摘要:

The oxidation of cyclohexene by ceric ammonium nitrate has been studied. In anhydrous DMSO the reaction leads to cyclohexene-3-nitrate, while in acetonitrileN-(cyclohexene-2-yl) acetamide is formed. Hydroxylated products are formed in the presence of water. The results obtained are explained in terms of the formation of an intermediate arising from the addition of the radical NO3•to the olefinic double bond. [Journal translation]

ISSN:0008-4042    

DOI:10.1139/v74-471

出版商:NRC Research Press    

年代:1974

数据来源: NRC