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1.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 51, No. 2, pp. 212–217, August, 1989. 相似文献
2.
G. S. Lyashenko A. Kh. Filippova I. D. Kalikhman G. G. Naumova N. S. Vyazankin 《Russian Chemical Bulletin》1982,31(11):2312-2314
Conclusions The addition of Et3GeH to the phenoxy- and phenylthioacetylenes under the influence of (Ph3P)3RhCl is both nonstereo- and nonregiospecific. The analogous reaction with 3-aroxy-1-propynes is stereospecific but nonregioselective.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2618–2620, November, 1982. 相似文献
3.
Reaction of benzothiazole-2-thione and benzothiazole-2-one with acetylene in the presence of potassium hydroxide or cadmium acetate gives 2-vinylthiobenzothiazole and 3-vinylbenzothiazol-2-one, respectively. Benzothiazole-2-thione is partially convened to benzothiazol-2-one by the action of Cd(OAc)2. Under vinylation conditions the latter also forms 2-vinylthioaniline.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 270–271, February, 1991. 相似文献
4.
L. B. Naumova L. A. Egorova A. A. Slivinskaya 《Russian Journal of Applied Chemistry》2006,79(2):236-240
The influence exerted by modifying additives of inorganic nature on the hydrophilicity of peats from the Orlovskoe deposit in Tomsk oblast and on their thermal stability was studied. The acid-base, equilibrium, and kinetic properties of the starting peat samples and those modified with solutions of iron(III) and aluminum chlorides were examined. Their physicochemical parameters were determined: total exchange capacity, acidity by acid and basic groups, relative humidity, distribution coefficients, effective diffusion coefficients, and activation energy. The effect of modifying cations on the thermal decomposition of peat was analyzed. 相似文献
5.
N. V. Kuratieva M. I. Naumova D. Yu. Naumov N. V. Podberezskaya 《Journal of Structural Chemistry》2004,45(2):281-286
Two modifications of hexaaquamagnesium(II) hypophosphite [Mg(H2O)6](H2PO2)2 have been synthesized and structurally characterized. Literature data are available for one of these forms. The geometrical characteristics of hexaaqua cations, hypophosphite anions, and nets of hydrogen bonds between the hypophosphite anions and the coordinated water molecules are analyzed. The packing motif of the structure-forming fragments was found to be the same for the two structures, except that modification of the inner structure of the complex cation leads to different nets of hydrogen-bonded cations and anions. 相似文献
6.
Natalia V. Kuratieva Marina I. Naumova Dmitry Yu. Naumov 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(9):i129-i131
The title compounds, hexaaquacobalt(II) bis(hypophosphite), [Co(H2O)6](H2PO2)2, and hexaaquacobalt(II)/nickel(II) bis(hypophosphite), [Co0.5Ni0.5(H2O)6](H2PO2)2, are shown to adopt the same structure as hexaaquamagnesium(II) bis(hypophosphite). The packing of the Co(Ni) and P atoms is the same as in the structure of CaF2. The CoII(NiII) atoms have a pseudo‐face‐centred cubic cell, with a = b~ 10.3 Å, and the P atoms occupy the tetrahedral cavities. The central metal cation has a slightly distorted octahedral coordination sphere. The geometry of the hypophosphite anion in the structure is very close to ideal, with point symmetry mm2. Each O atom of the hypophosphite anion is hydrogen bonded to three water molecules from different cation complexes, and each H atom of the hypophosphite anion is surrounded by three water molecules from further different cation complexes. 相似文献
7.
V. V. Kornienko G. Kh. Kitaeva I. I. Naumova A. N. Tuchak A. N. Penin P. V. Yakunin 《Optics and Spectroscopy》2014,116(4):520-528
Principal parameters of the nonlinear-optical crystals are analyzed, which govern the spectral sensitivity of the terahertz wave detectors based on the frequency conversion from terahertz to optical range. A method is developed and experimentally demonstrated for characterizing these parameters. The method is founded on the spontaneous parametric down-conversion spectra observation without external terahertz wave radiation. 相似文献
8.
M. V. Ryabukhina E. A. Kravtsov D. V. Blagodatkov L. I. Naumova V. V. Proglyado V. V. Ustinov Yu. Khaydukov 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2014,8(5):983-986
The magnetic structure of Fe/Cr/Gd superlattices is investigated using complementary methods of SQUID magnetometry and polarized neutron reflectometry. The complex magnetic behavior of the given system is caused by exchange interaction between the 3d (Fe) and 4f (Gd) layers of the ferromagnetic metals through the Cr antiferromagnetic spacer layer. It is found that a nonuniform profile of magnetization forms within the Gd layers under the influence of this interlayer interaction. 相似文献
9.
E. V. Guseva A. V. Sokolova A. M. Saifutdinov A. A. Naumova V. K. Polovnyak 《Russian Journal of General Chemistry》2012,82(5):827-834
The kinetics of homogeneous dehydrogenation of formic acid in the presence of supramolecular rhodium(III) complex with P-functionalized calix[4]resorcine were studied in dioxane, tetrahydrofuran, dimethylformamide, and binary formamide-dioxane mixtures (volume ratio 10: 90, 20: 80, 30: 70) over a wide temperature range (40?C90°C). The examined Rh(III) complex catalyzed the dehydrogenation process, and its catalytic activity was higher than that observed previously for rhodium complexes with non-macrocyclic phosphorus-containing ligands. The dehydrogenation rate constants were proportional to neither catalyst concentration nor dielectric constant of the medium, which is likely to be related to supramolecular nature of the Rh(III) complex. No micelle formation was observed in the examined systems. 相似文献
10.
Full wave profiles are used to determine the Hugoniot elastic limit and the spall strength of armco iron samples with an as-received structure and the samples recovered after preliminary loading by plane shock waves with an amplitude of 8, 17, and 35 GPa. The measurements are performed at a shock compression pressure below and above the polymorphic a–e transition pressure. Metallographic analysis of the structure of armco iron shows that a developed twinned structure forms inside grains in the samples subjected to preliminary compression and recovered and that the twin concentration and size increase with the shock compression pressure. The spall strength of armco iron under shock loading below the phase transition pressure increases by approximately 10% due to its preliminary deformation twinning at the maximum shock compression pressure. The spallation of samples with various structures at a shock compression pressure above the phase transition proceeds at almost the same tensile stresses. The polymorphic transition in armco iron weakly affects its strength characteristics. 相似文献