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Notes: Abstract The composition of the alkaloids in narcotic agents of domestic production (khanke) has been investigated by thin-layer and gas chromatographies. The retention times in GLC and the retention indices in TLC of the initial alkaloids and their acetylated derivatives have been determined. The rates of acetylation of the alkaloids have been evaluated with the aid of the GLC method.

Notes: Abstract Sulfonium salts are obtained by the reaction of cyclic sulfides with 1,4-benzoquinone and 5,8-quinolinedione in an acidic medium. It is shown by the method of concurrent reactions that the introduction of alkyl substituents into molecules of thiacyclopentane and thiacyclohexane decreases the reactivity of the sulfides. Quinolinedione is less reactive towards sulfides than is benzoquinone.

Notes: Conclusions 1. Complexes of rhenium with cyclic sulfur-containing ligands (thiophane, 2-propylthio-phane) catalyze hydrogenation and isomerization of olefin and diene hydrocarbons. 2. The catalytic activity of the complexes is a function of the ligand environment, the nature of the substrate, and the solvent. 3. The catalysts tested accelerate isomerization of α-olefins both in hydrogen and in an inert atmosphere with the predominant formation of cis-β-olefins.

Notes: Summary 1. A study has been made of the effect of compression at 20,000 aim on the properties of zinc oxide, titanium dioxide, thorium dioxide, and normal calcium phosphate in dehydrogenation and dehydration reactions characteristic for these catalysts. 2. It has beer, shown that as a result of compression the apparent specific volume of these catalysts is reduced by the factors indicated: Zinc oxide3.3 Titanium dioxide2.0 Thorium dioxide1.5 Calcium phosphate2.2 3. The selectivities in the action of zinc oxide in the dehydrogenation of isobutyl alcohol and in the action of calcium phosphate in the dehydration of formic acid were fully retained after compression. In the case of thorium dioxide also, compression had no effect on the relative rates of the two courses of the decomposition of ethyl alcohol. On the other hand. in presence of compressed titanium dioxide the ratio of the degree of dehydrogenation of alcohol to its degree of dehydration is lower than in presence of the noncompressed sample. It is probable that the change in the specificity of titanium dioxide due to compression is associated with change in its porosity characteristics and with the difficulty with which the dehydrogenation product (acetaldehyde) is desorbed from the catalyst. 4. In all cases the activation energy of the reaction is the same, whether the catalyst is compressed or not. 5. The activities of the investigated catalysts were altered in various ways by compression. The activity per unit weight was reduced for all catalysts apart from thorium dioxide, but the activity per unit volume rose for all catalysts except calcium phosphate, the activity of which was halved. 6. None of the investigated catalysts underwent any change in crystal structure when compressed. I am grateful to A. M. Rubinshtein for the X-ray analysis of the catalysts.

Notes: Summary 1. An investigation has been made of the effect of pressures of up to 20,000 arm on the porosity characteristics adsorption activity, and catalytic properties of silica gel. 2. It has been shown that the greatest reduction (by 50%) in the limiting sorptive capacity of the pores (sum of the capacities of the micro and connective pores of the coarsely porous silica gel) occurs during compression to 5000 atm, but no simultaneous change in specific surface occurs. The greatest reduction in the limiting sorptive capacity of the pores of the finely porous silica gel occurs over the range 5000-10,000 atm. The reduction in the limiting sorptive capacity of the pores is therefore attained by a lower compression for the coarsely porous silica gel.The explanation of this is that the coarsely porous silica gel, unlike the finely porous material, has a greater volume of connective pores. Mechanical action, therefore, primarily destroys the connective pores, whereas thermal action destroys the fine pores. In general, the limiting sorptive capacity of the coarsely porous silica gel compressed at 5000-10,000 atm does not differ, from that of the finely porous material, i.e., the coarsely porous material is converted by pressure into finely porous material. When the compression is further increased to 20,000 atm, the limiting sorptive capacity, of the pores of the samples of finely and coarsely porous silica gels remains practically the same as that of the samples, compressed at 10,000 atm. 3. Compression at 20,000 atm results in reduction of the specific surface of coarsely porous silica gel from 350 to 260 sq.m/g, and that of the finely porous silica gel from 680 to 290 sq.m/g, i.e., by 26% and 57%, respectively. 4. The productivity of samples compressed at 5000 atm is higher, and of those compressed at 20,000 atm lower, than that of the uncompressed sample. The greater the compression, the lower the specific activity. 5. The selectivity of samples compressed at 5000 atm differs little from that of the uncompressed sample, but samples compressed at higher pressures have greatly reduced selectivity. it is possible that samples that have been subjected to higher compression, i.e. have a more severely destroyed porous structure, more readily sinter together, and so become deactivated. 6. It has been shown that the chromatographic activity of silica gel compressed at 20,000 atms about 25% less than that of the uncompressed sample.