Formation of carbon dioxide and water during removal of hazardous impurities from gases

The reliability of experimental data on the formation of carbon dioxide and water during gas purification is verified. The previously proposed gas purification scheme based on oxidation of gas decomposition products is revised in light of data obtained by thermodynamic computations. Monoatomic oxygen is found to participate in oxidation.     

On the eigenvalues of a 3 by 3 non-Hermitian Hamiltonian

In this paper, we are concerned with a 3 × 3 complex matrix Jacobi (tri-diagonal matrix) arised from a non-Hermitian discrete quantum system. Necessary and sufficient conditions for reality of the eigenvalues of the matrix in question are established.     

Catalytic methylation of phenol

Attempt was made to methylate phenol with methyl formate in the presence of a zeolite-supported palladium and a ruthenium-titanium catalyst.     

Selective modulation of infrared radiation by an Al2O3 particles — liquid crystal system

We have developed a dual-frequency liquid crystal consisting of 4-n-pentyl-4′-cyanobiphenyl (5CB), 4-hexyloxyphenyl-4′-hexyloxy-3-nitrobenzoate (C2), and 4-butyl-4′-(hexyloxyphenyloxycarbonyl)phenyl carbonate (H22). We have measured the frequency dependences of the longitudinal and transverse components of the dielectric constant of the mixture and we have determined the frequency regions of positive and negative dielectric anisotropy. We show that for certain changes in the frequency of the applied electric field while the magnitude of the field remains the same, the transmission region of the Al₂O₃ particles — dual-frequency liquid crystal system switches from one wavelength to the other. The experimental results are explained by the optical homogeneity of the system in a narrow wavelength interval when the refractive indices of the particle material and the matrix are close, and also by reorientation of the liquid crystal molecules as the frequency of the applied voltage changes.     

On exceedances of record and order statistics

Exact, limiting distributions along with their rates of convergence of exceedance statistics for both order statistics and record statistics are provided when the underlying distribution is arbitrary. The exact distribution of record statistics for arbitrary underlying distributions is obtained as well.

     

Study of radical copolymerization of aminomethylated derivatives of alkenylphenols with styrene

Aminomethylated derivatives 2-propenyl-, 2-allyl-, and 4-isopropenylphenols are studied as comonomers in free-radical copolymerization with styrene in bulk. As evidenced by NMR studies, in o-aminomethyl derivatives of alkenylphenols, stable intramolecular hydrogen bonds form between nitrogen atom of the aminomethyl fragment and hydrogen atom of the hydroxyl group; these bonds are not destroyed up to 80°C Therefore, these compounds may be involved in free-radical copolymerization with styrene in which the inhibiting effect of OH groups is avoided at a temperature of 60°C. The values of r ₁ and r ₂ are determined for two pairs of comonomers: 6-morpholinomethyl-2-propenylphenol and styrene (r ₁ = 0.20 ± 0.01 and r ₂ = 2.40 ± 0.04) and 2-allyl-6-morpholinomethylphenol and styrene (r ₁ = 0.090 ± 0.009 and r ₂ = 2.40 ± 0.04).     

Mechanism of electric spark dispersion of aluminum in aqueous solutions

Aluminum electroerosion was continued to be studied. The obtained experimental data confirmed the validity of the previously proposed mechanism of electric spark dispersion of aluminum. The composition of the oxide film forming on the surface of dispersed metal particles depends on the amount of atomic oxygen produced during electroerosion.     

High-resolution Raman scattering in oligonucleotides

The high-resolution spectra of short single-stranded oligonucleotides have been measured by the high-sensitivity nonresonant Raman scattering method using the example of the system d(20G, 20T), where G is guanine and T is thymine. The samples under study have been prepared by the chemical synthesis using the solid-phase amidophosphite method on an automatic synthesizer. It has been shown that the spectra observed in the frequency range of 500–1500 cm^?1 can be sufficient for the resolution of spectral components corresponding to vibrations of individual oligonucleotide molecules, which contain a large number of atoms in the unit cell.