摘要:

The electrical conductivity of germanium(II) sulfide in the liquid state has been measured with a capillary-type cell. Both a-c. and d-c. methods were used. The conductivity of liquid GeS increases regularly with tempersature from 1.33 Ω−1 cm−1at 664 °C to 2.52 Ω−1 cm−1at 705 °C. The experimental facts lead to the conclusion that GeS remains a semiconductor in the liquid state with a conduction band situated at 2.5 eV above the valence band.The energy gaps of GeS, SnS, and PbS in the solid state are compared with those of the corresponding liquids. It is concluded that these sulfides, in the liquid state, have structures very similar to that of the solids. Liquid PbS has a structure somewhat similar to that of metals. In the case of SnS and GeS, heating and melting are accompanied by a gradual loosening of the double layers which constitute the crystals. Accumulated evidence indicates that the molecular character of SnS and GeS is increased on going from the solid to the liquid state.

ISSN:0008-4042    

DOI:10.1139/v66-126

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

The thermal oxidation of styrene inhibited by diphenylamine, phenyl-α-naphthylamine, and phenyl-β-naphthylamine has been examined. It has been shown that the autocatalysis of the diphenylamine- and phenyl-β-naphthylamine-inhibited oxidations is probably due to a reaction between the inhibitor radical and the hydroperoxide formed in the primary step of inhibition. This reaction is too slow to produce significant autocatalysis with phenyl-α:-naphthylamine under the present experimental conditions.The primary inhibition reaction involves abstraction of the amino hydrogen since its replacement by deuterium leads to a fairly large kinetic isotope effect (kH/kD ~ 3–4).

ISSN:0008-4042    

DOI:10.1139/v66-127

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

Hydrogen gas partly dissociated in an electrodeless discharge was mixed downstream with hydrogen peroxide vapor at low pressure (0.1 mm Hg) in a liquid nitrogen trap. The reaction products condensed readily on the wall as a clear, yellowish glass resembling that from dissociated water vapor and other related systems. A manometric study of the warming-up process has revealed four distinct steps. The first two, in which only traces of gas are given off, look like the recombination of trapped free radicals. The major evolution of oxygen upon crystallization of the glassy deposit at 160 °K is ascribed to the decomposition of hydrogen peroxide under the influence of some unidentified species generated in the electric discharge through hydrogen. Experimental evidence for this is presented. In any case the stoichiometry cannot be reconciled with the formation of a metastable intermediate, such as the hypothetical polyoxide H2O4.In the last step beginning around 215 °K more peroxide is decomposed during the eutectic melting of the solid. Qualitatively these phenomena are similar to those shown by the condensate from dissociated water vapor.

ISSN:0008-4042    

DOI:10.1139/v66-128

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

Seven mixed hydroxides of magnesium and aluminium were prepared, and phase and structural changes accompanying their dehydration were investigated by differential thermal analysis, thermogravimetric analysis, and X-ray diffraction techniques. The differential thermal analysis curves possess 2 peaks corresponding to those of parent hydroxides together with a new peak, and the thermogravimetric analysis curves show slight inflections. X-ray diffraction patterns of the mixed hydroxides possess the characteristic lines of the parent hydroxides together with three to five new intense lines which might indicate the formation of a double hydroxide. When the mixed hydroxides are progressively heated they give rise to products possessing patterns which first become diffuse and ultimately pass mainly into the spinel pattern.Adsorption isotherms of cyclohexane and benzene were measured on the mixed hydroxides and their dehydration products. Specific surface areas calculated by the application of the Brunauer, Emmett, Teller (B.E.T.) equation are in general in good agreement for the two adsorbates. The surface area increases with rise of dehydration temperature to a maximum at 500–600 °C and then decreases with further rise in temperature. This behavior is common to crystalline oxide systems and may be ascribed to the intermingling of decomposition, re-crystallization, and sintering processes. Variations in the molecular ratio of the mixed oxides (as much as 20-fold), and in the method of preparation, do not much alter the surface area.

ISSN:0008-4042    

DOI:10.1139/v66-129

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

The first stages in an intensive study of Szilard–Chalmers recoil reactions in a covalent metal-organic compound are described. The radioactive manganese-56 is found, as expected, as inorganic manganese (75–80%), as the parent compound (12–20%), and as one or other of two hitherto unidentified, unstable compounds depending on whether anhydrous paper chromatography or paper ionography is used as the separation method (5–7%). Some data are given showing the effect of room-temperature annealing following irradiation at −196 °C. In particular, the yield of one of the unidentified compounds increases markedly (to ~15%) while that of the other compound remains nearly unaffected.Thin-layer chromatography in anhydrous benzene was used as separation method in thermal annealing studies. They show two hitherto unreported phenomena: The apparent retention increases considerably and then decreases again as annealing continues, and the annealing reaction at two temperatures in the liquid and one in the solid phase are qualitatively very similar. These results are interpreted as indicating the presence of another species, the "pseudoparent", which is not distinguished chromatographically from the parent. Some discussion is given as to possible mechanisms.

ISSN:0008-4042    

DOI:10.1139/v66-130

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

Coordination complexes of copper(II) acetate, ammonia, aliphatic amines, and pyridine have been prepared. Molecular formulae on the basis of percentage of constituent elements were found to be Cu(OAc)2(am)2, where OAc represents acetate ion and am any amine used. Conductivity measurements in nitrobenzene and formamide indicate that the complexes are nonelectrolytes and thus it is suggested that acetate ions are also coordinated. Molecular weight measurements in the same solvents confirm this. Visible absorption measurements in formamide show a single band at about 635 mμ.

ISSN:0008-4042    

DOI:10.1139/v66-131

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

Proton nuclear magnetic resonance spectra of BF3, BCl3, and BBr3adducts of acetonitrile have been measured in nitrobenzene solution. Single peaks were observed in each case and chemical shifts relative to tetramethylsilane decreased in the order BBr3 > BCl3 > BF3, suggesting that this is the order of acceptor activity toward acetonitrile. Linear relationships exist between methyl proton chemical shifts of CH3CN•BX3and the heats of formation, dipole moments, and infrared vibrational shifts of the same or related adducts.

ISSN:0008-4042    

DOI:10.1139/v66-132

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

The reactions of a series of fluorinated olefins with hexamethylditin have been investigated, under conditions which favor the formation of (CH3)3Sn• radicals. Two principal types of products have been isolated, namely (polyfluoroalkyl)trimethyltin compounds, e.g. (CH3)3SnCF2CF(R)H, and insertion products of the type (CH3)3SnCF2CF(R)Sn(CH3)3, where R = F or CF3. These results are consistent with the formation of intermediate radicals such as (CH3)3SnCF2C(R)F• which then participate either in hydrogen abstraction or in the formation of the insertion products. Reactions of hexamethylditin with CF2=CFH, CF2=CH2, CF2=CFCl, CF2=CFBr, and C2H4are also discussed. The direction of attack of the (CH3)3Sn• radical on the olefins indicates that the former has a high degree of nucleophilic character. A more detailed study of the reactions of the cyclic hexamers of dimethyltin and diphenyltin with tetrafluoroethylene shows that some addition does occur, but that the products are of indeterminate composition. The reaction of hexameric dimethyltin with trifluoroiodomethane has also been examined.

ISSN:0008-4042    

DOI:10.1139/v66-133

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

A study of the equilibrium freezing-point diagram for the system acetone–bromoform shows that no solid-phase compound forms between acetone and bromoform. The diagram is of the simple eutectic type, the eutectic lying at −101° and 84 mole % acetone. The enthalpies of mixing have been determined for various compositions of mixture and the numerical value of ΔH(per mole of acetone or bromoform) extrapolated to infinite excess of bromoform or of acetone, to obtain the value for completely undissociated complex. This figure is −1.3 kcal per mole of complex (assumed mole to mole). The dipole moments, excess volumes of mixing, viscosities, and total and partial vapor pressures of the system have been measured. From these data, the excess free energy and excess entropy and other thermodynamic functions have been evaluated.

ISSN:0008-4042    

DOI:10.1139/v66-134

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

The conductances, densities, and viscosities of aqueous solutions of sodium chlorate were determined over the complete range of concentration at 25 °C and at 35 °C. An attempt was made to reproduce the results at 25 °C with the viscosity-corrected Falkenhagen–Leist and Wishaw–Stokes equations. The limiting equivalent conductances of sodium chlorate at 25 °C and 35 °C in water were also determined.The conductances, densities, and viscosities of sodium chlorate at 25 °C and 35 °C were determined in a solvent consisting of 64.5% dioxane, 35.5% water. The limiting equivalent conductances of sodium chlorate at 25 °C and 35 °C and of lithium chlorate at 25 °C in this solvent were determined by analyzing the data with the Fuoss–Onsager equation for associated electrolytes.Finally, conductances of sodium chlorate and lithium chlorate at 25 °C were determined in a solvent consisting of 90% dioxane, 10% water.

ISSN:0008-4042    

DOI:10.1139/v66-135

出版商:NRC Research Press    

年代:1966

数据来源: NRC