摘要:

A study was made of the influence of diluent gases on the reaction rate and activation energy of the oxidation of sulfur dioxide over vanadium pentoxide catalyst, an effect noted by Baron, Manning, and Johnstone in 1952. Results confirmed the occurrence of the effect in a still lower temperature range (350–470 °C). Using non-adsorbing gases, helium and argon, the effect was demonstrated to be free from chemisorption of the diluents.Data on activation energy vs. molecular weight of the gas phase, using helium and argon, were in qualitative agreement with predictions based on a momentum-exchange model of Baronetal. However, comparison of rates obtained with argon (monatomic) and nitrogen (diatomic) as diluents, combined with independent study of the rate controlling steps, casts doubt on the adequacy of the explanation offered by Baronetal.

ISSN:0008-4042    

DOI:10.1139/v70-195

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

Infrared and Raman spectra have been recorded for room-temperature-phase, powdered samples of LiNO3, NaNO3, KNO3, RbNO3, CsNO3, AgNO3, and TlNO3. For the trigonal systems, the nitrate pairs LiNO3, NaNO3and RbNO3, CsNO3give almost identical spectra. For the orthorhombic systems, AgNO3and TlNO3give similar spectra, whereas that of KNO3is significantly different. Site and correlation field perturbations are considerably more pronounced in the antisymmetric stretching region (ν3ca. 1400 cm−1) than in the antisymmetric bending region (ν4ca. 700 cm−1). Although lifting of the degeneracy ofE′ modes was frequently observed, the reported split of the ν4(E′) mode (ca. 716 cm−1) of the aragonite form of KNO3could not be confirmed. Multiple internal reflectance techniques have been employed to observe the extremely intense ν3(E′) infrared fundamental ca. 1400 cm−1.

ISSN:0008-4042    

DOI:10.1139/v70-196

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

Infrared and Raman spectra of powdered ionic nitrates contain low intensity vibrational bands which are assigned to isotopically different species. Bands at ~(ν1 − 20) and ~ (ν4 − 13) cm−1are assigned to the14N16O218O−ion whereas the band at ~ (ν2 − 20) cm−1is assigned to the15N16O3−ion. Failure of the ratio of band intensities to agree with predicted isotopic ratios is discussed.

ISSN:0008-4042    

DOI:10.1139/v70-197

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

Raman, infrared, and proton magnetic resonance spectra of solutions of zinc nitrate in anhydrous methanol are reported. It is concluded that above −30 °C the zinc and nitrate ions can form contact ion-pairs, but that below −30 °C association is limited to the formation of solvent-separated ion-pairs. The apparent solvation number of zinc, as determined by area measurements on the proton magnetic resonance spectra, decreases with increasing solute concentration, and an interpretation of this effect is given.

ISSN:0008-4042    

DOI:10.1139/v70-198

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

Arrhenius parameters have been measured for H abstraction from the alkylchlorosilanes CH3SiCl3, (CH3)2SiCl2, and (CH3)3SiCl, and also for (CH3)4Siwherekis in ml mole−1s−1. Halogen abstraction does not occur with these compounds nor with SiCl4. CF2CH2is formed from the hot molecule produced when the silylmethyl radical combines with CF3

ISSN:0008-4042    

DOI:10.1139/v70-199

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

Viscosity data for ammonia, methylamine, and 1,2-diaminopropane have been obtained in the temperature ranges −65 to −35, −65 to −10, and −35 to +50 °C, respectively, using an Ubbelohde viscometer. The results were compared with existing data, and all the data were fitted to the Fulcher (Tammann–Hesse) equation by the method of least squares. The significance of the values ofT0in this equation for these and other associated liquids was considered.

ISSN:0008-4042    

DOI:10.1139/v70-200

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

The preparation of 1,5-biscarbethoxybicyclo[3.2.2]nonane and 1,5-bis(hydroxymethyl)bicyclo[3.2.2]nonane is described. The procedure generally followed that reported for the analogous bicyclo[2.2.2]octanes. However, certain differences in chemical behavior were observed and are reported.The alkylation of the sodium salt of diethyl succinylsuccinate produced the expected 1,5-biscarbethoxybicyclo[3.2.2]nonane-6,8-dione along with a by-product which was shown to be 1,5-biscarbethoxybicyclo[4.2.1]nonane-7,9-dione. It was also shown that this compound arose by isomerization of the bicyclo[3.2.2]nonane analogue after the alkylation occurred.Conversion of these compounds to thioketals with 1,3-propanedithiol was also examined in detail. The reaction between 1,3-propanedithiol and 1,5-biscarbethoxybicyclo[3.2.2]nonane-6,8-dione generated an equilibrating system of 4 compounds. Three of these are shown to be the monothioketal, the bisthioketal, and a mixed thioketal–vinylthioether.

ISSN:0008-4042    

DOI:10.1139/v70-201

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

not available

ISSN:0008-4042    

DOI:10.1139/v70-202

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

The radiation-induced oxidation of 2-propanol by hydrogen peroxide in neutral deaerated aqueous solution has been investigated. 2-Propanol is oxidized to acetone, and hydrogen peroxide reduced in stoichiometrically equivalent high yields. The yields are independent of hydrogen peroxide concentration in the range 5 × 10−2to 10−3 Mand linearly dependent on alcohol concentration in the range 0.13 to 1.05 M. The reaction yields increased with decreasing dose rate.The results are explained by a chain mechanism in which initiation occurs via H-atom abstraction from 2-propanol to form either (CH3)2ĊOH (1) or CH3CHOH ĊH2(2).1reacts with H2O2in a chain propagating reaction2may abstract the α hydrogen from the parent alcoholor undergo bimolecular termination. A lower limit of 53 ± 101mole−1s−1is estimated for the rate constant for this radical conversion reactio

ISSN:0008-4042    

DOI:10.1139/v70-203

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

The preparation and characterization of the compounds Se8(Sb2F11)2and Se8(AsF6)2are described. Both compounds are shown to contain the Se82+cation.

ISSN:0008-4042    

DOI:10.1139/v70-204

出版商:NRC Research Press    

年代:1970

数据来源: NRC