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41.
The rapid gas chromatographic detection and determination of ethylene glycol in biological fluids is described. Phenylboronic acid in acetone was used for the esterification of glycol. The phenylboronates of ethylene glycol and 1,2-propylene glycol are not separated on a packed column of medium polarity (OV-17), but they can be separated on a non-polar column (OV-101). In both instances, 1,3-propylene glycol can be used as an internal standard. The method requires only 100 microliters of serum or urine and is suitable for trace analysis in an emergency toxicological laboratory. The utility of the method is demonstrated on two cases of human intoxication with ethylene glycol. 相似文献
42.
L. N. Raevskaya N. I. Il’chenko Yu. I. Pyatnitskii N. V. Pavlenko 《Theoretical and Experimental Chemistry》1997,33(2):78-81
The catalytic transformation of methane into higher hydrocarbons was studied under unsteady conditions on oxides of various
metals (Pb, Fe, Nb, Ti, Cd, Mo, Mg, Zn, Zr, Bi, Mn), and also on Sr-, La-, Y-, and Mn-containing oxides of perovskite structure.
It is shown that the effectiveness of the catalysts not only depends on their chemical composition, but also is determined
to a considerable degree by the specific surface of the oxides.
L. V. Pisarzhevskii Institute of Physical Chemistry, Academy of Sciences of Ukraine, 252039 Kiev, Prosp. Nauki, 31, Ukraine.
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 33, No. 2, pp. 91–95, March–April, 1997. 相似文献
43.
θ-Conditions, the temperature coefficient of unperturbed dimensions of the macromolecules and the thermodynamic interaction parameters ψ and κ were determined for solutions of poly(methyl methacrylate) in 2-alkoxyethanols (methoxy, ethoxy and butoxy). The results for this series of solvents fit the data reported for other solvents and dln . The dependence of parameters ψ and κ exhibited deviations from the theoretical dependence, mainly near the limiting value ψ = 0.5. 相似文献
44.
M. O. Manukyan A. V. Babakhanyan G. A. Panosyan A. Kh. Gyul’nazaryan S. T. Kocharyan 《Russian Journal of General Chemistry》2007,77(8):1370-1372
Ammonium salts containing phenacyl group in combination with 4-allyloxy(phehoxy)-2-butynyl group, when treated with a suspension of potassium hydroxide in benzene, undergo the 3,2-Stevens rearrangement with the formation of allenic amino ketones which under the reaction conditions give the furan derivatives. 相似文献
45.
A. A. Ol’shanskaya N. A. Sobgaida S. S. Popova 《Russian Journal of Applied Chemistry》2004,77(9):1505-1509
The influence of temperature, duration of thermal treatment, and oxidation modes of the aluminum base on processes in which intermetallic compounds LiLaAl are formed by the method of electrochemical cathodic intercalation was studied. The optimal modes of formation of LiLaAlox compounds exhibiting high sorption capacity for hydrogen were determined.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 9, 2004, pp. 1516–1519.Original Russian Text Copyright © 2004 by Olshanskaya, Sobgaida, Popova. 相似文献
46.
L. I. Kas’yan S. I. Okovityi I. N. Tarabara A. O. Kas’yan Ya. S. Bondarenko 《Russian Journal of Organic Chemistry》2005,41(6):816-824
4-Azatricyclo[5.2.1.02,6]dec-8-ene was synthesized and brought into reactions with benzoyl, o-chlorobenzoyl, p-bromobenzoyl, p-, m-, and o-nitrobenzoyl, and bicyclo[2.2.1]hept-2-ene-endo-5,endo-6-dicarboximidoacetyl chlorides in chloroform in the presence of pyridine. The tricyclic amides thus obtained were epoxidated with peroxyphthalic acid prepared in situ by reaction of phthalic anhydride with a 35% aqueous solution of hydrogen peroxide. The structure of newly synthesized compounds was confirmed by IR and 1H and 13C NMR spectroscopy and mass spectrometry. Their NMR spectra were compared with those of previously synthesized N-arylsulfonyl-4-azatricyclo[5.2.1.02,6]dec-8-enes on the basis of conformational composition of the corresponding p-nitrophenyl-substituted derivatives, which was determined by PM3 semi-empirical quantum-chemical calculations.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 6, 2005, pp. 837–845.Original Russian Text Copyright © 2005 by L. Kas’yan, Okovityi, Tarabara, A. Kas’yan, Bondarenko. 相似文献
47.
M. Mrnka V. Jedináková J. Sladkovská 《Journal of Radioanalytical and Nuclear Chemistry》1974,21(1):87-95
The results of the extraction of HCl by TDPO in benzene and the co-extraction of water are discussed. From the infrared spectra
of normal (HCl-H2O) and deuterated (DCl-D2O) systems it may be concluded that TDPO·HCl·H2O is formed in the organic phase on extraction from aqueous solutions with cHCl≤5M, and TDPO·HCl with cHCl>5M. Compounds such as TDPO·2HCl are found in the organic phase if there is an excess of HCl in the organic phase. From cryoscopic
and viscosity measurements of the organic phase, conclusions can be made about the presence of polymeric compounds in this
phase. 相似文献
48.
A. V. Klinov G. S. D’yakonov A. V. Malygin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2007,81(12):1945-1949
Integral equation theory for partial distribution functions was used to suggest an effective method for calculating the derivative of radial distribution function with respect to temperature under isobaric conditions. The thermodynamic expansion, compression, and pressure coefficients and isobaric and isochoric heat capacities were calculated for Lennard-Jones fluids. The calculation results were in close agreement with the known thermodynamic relations. 相似文献
49.
S. A. Mikhalenko L. I. Solov’eva E. A. Luk’‘yanets 《Russian Journal of General Chemistry》2004,74(11):1775-1800
Procedures have been developed for the synthesis of a series of metal complexes derived from water-soluble anionic and cationic octa-4,5-carboxyphthalocyanine-taurine and choline conjugates.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 11, 2004, pp. 1907–1911.Original Russian Text Copyright © 2004 by Mikhalenko, Soloveva, Lukyanets.For communication XXXVII, see [1].This revised version was published online in April 2005 with a corrected cover date. 相似文献
50.
A. M. Makarevich P. R. Abdyushev N. M. Sorokina I. E. Korsakov N. P. Kuz’mina 《Russian Journal of Coordination Chemistry》2006,32(10):707-711
A reaction of samarium oxide, nickel oxocarbonate, and diethylenetriaminepentaacetic acid (H5DTPA) taken in stoichiometric proportions in water gave SmNiDTPA · 10H2O as a glassy solid. The formation of this heterometallic complex was confirmed by data from elemental analysis, IR spectroscopy, thermal analysis, and X-ray fluorescence analysis. An aqueous solution of the complex was used to deposit SmNiO3 films onto a single-crystal SrTiO3(001) substrate. The SmNiO3 phase in films obtained upon 3-h annealing at 500°C was identified by powder X-ray diffraction. Films deposited from a solution of an equimolar mixture of monometallic samarium and nickel diethylenetriaminepentaacetates contained no samarium nickelate. 相似文献