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101.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, p. 2186, September, 1988.  相似文献   
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Conclusions A method was developed for the chromatographic separation of the alkyl derivatives of pyrocatechol employing thin-layer chromatography on plates.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2816–2817, December, 1971.  相似文献   
106.
The properties of harmonic surface waves in an elastic cylinder made of a rigid material and filled with a fluid are studied. The problem is solved using the dynamic equations of elasticity and the equations of motion of a perfect compressible fluid. It is shown that two surface (Stoneley and Rayleigh) waves exist in this waveguide system. The first normal wave generates a Stoneley wave on the inner surface of the cylinder. If the material is rigid, no normal wave exists to transform into a Rayleigh wave. The Rayleigh wave on the outer surface forms on certain sections of different dispersion curves. The kinematic and energy characteristics of surface waves are analyzed. As the wave number increases, the phase velocities of all normal waves, except the first one, tend to the sonic velocity in the fluid from above __________ Translated from Prikladnaya Mekhanika, Vol. 43, No. 9, pp. 48–62, September 2007.  相似文献   
107.
New complex sodium lanthanide phosphate molybdates Na2MIII(MoO4)(PO4)(MIII=Tb, Dy, Ho, Er, Tm, Lu) have been synthesized by the ceramic method (T = 600°C, τ = 48 h), and their unit cell parameters have been determined. The structures of Na2MIII(MoO4)(PO4)(MIII = Dy, Ho, Er, Lu) were refined by the Rietveld method. The compounds are isostructural: they are orthorhombic (space group Ibca, Z = 8) and have layered structures. In the structures of phosphate molybdates, chains of MIIIO8 polyhedra and MoO4 tetrahedra are linked by PO4 tetrahedra to form layers. The MoO 4 2? anions are involved in dipole-dipole interaction. The sodium ions are arranged in the interlayer space. The compounds melt incongruently at 850–870°C.  相似文献   
108.
Adiabatic calorimetry is used to measure the low-temperature heat capacity of Na2Er(MoO4)(PO4)from 6.41 to 347.87 K. Experimental data are used to calculate the thermodynamic functions of Na2Er(MoO4)(PO4), which at 298.15 K are as follows: C p 0 (298.15 K) = 243,3 ± 0.4 J/(K mol), S 0(298.15 K) = 312.8 ± 0.8 J/(K mol), H 0(298.15 K) ? H 0(0 K) = 45280 ± 90 J/mol, and Φ0(298.15 K) = 136.1 ± 0.3 J/(K mol). A diffuse heat-capacity anomaly associated with splitting of the Stark levels (Schottky anomaly) is discovered in the low-temperature region.  相似文献   
109.
The stability of 3,5-di-tert-butylsalicylic aldehyde against oxidation is due to autoinhibiting of the chain process. However its oxidation into 3,5-di-tert-butylsalicylic acid was performed at the use of acetyl protection of the hydroxy group. In reaction of 6-bromo-2,4-di-tert-butylphenol with urotropin the formation was discovered of 3,5-di-tert-butylsalicylic acid, its nitrile and amide.  相似文献   
110.
Solid-phase oxidation of 2,4-di-tert-butylphenol to give 2,2′,4,4′-tert-butyl-6,6′-bisphenol and of 3,6-di-tert-butylpyrocatechol to afford 3,6-di-tert-butyl-l,2-benzoquinone was performed in the presence of alkali and alkaline earth metals halides under conditions of modified extrusion. The formation of the corresponding metal 3,6-di-tert-butylsemiquinolates was registered by ESR method. The different behavior of chlorides, bromides, and iodides was observed and rationalized basing on the dissimilar complexing ability of halogens. The mechanism of activated oxidation was assumed. The study was carried out under financial support of the Russian Foundation for Basic Research (grant no. 96-03-33253a). Deceased.  相似文献   
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