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11.
The total, ionic, and protonic conductivities of solid electrolytes BaCe0.85R0.15O3 – (BC15R), where R = Sc, Y, La, and all lanthanides bar Pm, are studied at 2 = 2.1 × 104–10–15 Pa, 2 = 2.1 × 103 Pa, and temperatures of 550–1000°. The samples are synthesized in air at 1450° for two hours. In oxidizing media, all the electrolytes are mixed ion–hole conductors. In reducing environment, BC15R doped with R3+ exhibit oxygen–proton conduction. Ionic and protonic conductivities are independent of 2. Protonic conductivity disobeys the Arrhenius dependence: it decreases with increasing temperature. The total and ionic conductivities of BC15R are virtually independent of the nature of cations R3+ in the interval from Nd to Lu.  相似文献   
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Diphosphorus-substituted isoxazole and 1,2,3-triazole were synthesized by a click chemistry method. Their polarity and structure were determined by the dipole moment method and quantum chemical calculations.  相似文献   
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A new alkaloid has been isolated from the epigeal part ofConvolvulus krauseanus Regel. et Schmalh., and its structure has been established as (±)-3-veratroyl-N-hydroxynortropane.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 749–751, November–December, 1983.  相似文献   
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As shown by the dipole moment method and quantum chemical calculations, (arylcarbamoylmethyl) diphenylphosphine oxides and sulfides exist as equilibrium mixtures of several rotational isomers stabilized by H · · · X intramolecular hydrogen bonds (X = O, S). The most energetically favorable rotamer and its fraction have been determined for each compound.  相似文献   
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A method for preparingN-(imidomethyl)glycine esters by the reaction of alkyl glycinates with formaldehyde and imides has been developed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1306–1307, July, 1995.  相似文献   
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The radioastronomical method CLEAN is extended to problems of three-dimensional (3D) tomographic reconstruction. We consider two options, namely, 3D1D (reconstruction using one-dimensional projections) and 3D2D (reconstruction based on using two-dimensional projections). Deconvolution with the use of the synthesized beam (equivalent total transfer function) makes it possible to reduce several times the number of aspects in comparison with the conventional approach. We point out the relationship between the maximum level of sidelobes of the synthesized ray constructed for the Gaussian transfer functions and the number of used projections. In the case of 3D2D -reconstruction, the reconstruction quality similar to that for the 2D1D case is only achieved if the same number of uniformly distributed projections are used in both cases. The use of one-dimensional projections for the 3D1D -reconstruction requires doubling of the number of projections. The reconstruction process is illustrated by an example of the three-dimensional model of an optically thin radiating object. We consider the possibilities of using the developed approach in astrotomography and remote sensing based on introducing the transfer functions which determine resolution of the receiving beam patterns and spectrographs, as well as temporal resolution of the sensing profiles. __________ Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 48, No. 5, pp. 367–381, May 2005.  相似文献   
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The extraction of trace amounts of scandium(III) from HCl,HNO3, and HClO4 solutions in the form of complexes with neutral polyfunctional organophosphorus compounds bis(diphenylphosphorylmethylcarbamoyl)alkanes [Ph2P(O)CH2C(O)NH]2(CH2) n (n = 3, 5, 8) was studied. The effect of the structure of the extractant, the aqueous phase composition, and the nature of the organic solvent on the efficiency of transition of scandium(III) ions into the organic phase was considered, and the stoichiometry of the extracted complexes was determined. The studied ligands exhibit a higher extraction power toward scandium(III) ions than their analog Ph2P(O)CH2C(O)NHC9H19 containing only one bidentate carbamoylmethylphosphoryl moiety per molecule. Scandium(III) passes into the organic phase most efficiently in the presence of HClO4 in the aqueous phase. It was shown that scandium(III) can be selectively recovered and preconcentrated by a complexing adsorbent obtained by noncovalent immobilization of bis(diphenylphosphorylmethylcarbamoyl)pentane on a macroporous polymer matrix.  相似文献   
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