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81.
Lahcène Ouahab Stéphane Golhen Smaïl Triki Andrzej Łapiński Mykola Golub Roman Świetlik 《Journal of Cluster Science》2002,13(3):267-278
A new charge transfer salt based on bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) and the vanadium substituted Lindquist anion [VW5O19]3– was synthesized and characterized by X-ray and spectroscopic analysis. Monoclinic, C2, F
w
=3789.2, a=41.5019(5), b=11.2600(2), c=12.7514(2) Å, =101.877(5)°, Z=2, R=0.060, based on 12095 reflections with I>2(I). The structure consists of alternating organic and inorganic layers. The inorganic layer is generated by [VW5O19]3– anions, dimethylformamide (DMF) and water molecules. The organic layer, which is generated by three different BEDT-TTF units, belongs to the -type of packing and consists of trimerized chains parallel to the c direction. The compound is a semi-conductor with
300 K
=1.1 Scm–1 and E
a
=0.1 eV. Polarized reflectance spectra of single crystals were measured over the spectral range from 650 to 25000 cm–1. FT-NIR Raman spectra of powdered crystals dispersed in KBr pellets were also recorded. Vibrational and electronic features are discussed. 相似文献
82.
Template-derived mesoporous carbons with highly dispersed transition metals as media for the reactive adsorption of dibenzothiophene 总被引:1,自引:0,他引:1
Mesoporous carbons with highly dispersed copper, cobalt, and iron were obtained from an organic polymer within amorphous silica powder, alumina, and zeolite 13X. The materials were characterized using the adsorption of nitrogen, potentiometric titration, and elemental analysis. The small metal content (less than 1%) and its chelation in the precursor polymers ensure a high dispersion of metallic centers. The materials obtained are mainly mesoporous but differ significantly in their porosity and surface chemistry, which is linked to the effect of template constraints and chemistry and the kind of metal and is related to the differences in the carbonization mechanism. On the carbon obtained, the adsorption of dibenzothiophene (DBT) from hexane was carried out. The high capacities (up to 130 mg S/g) obtained were linked to the high volume of mesopores and specific interactions of DBT with surface acidic groups and strong interactions of metals with dibenzothiophene via S-M sigma bonds or, in the case of copper, via interaction of metals with disturbed pi electrons of aromatic rings of DBT. 相似文献
83.
Vasyl S. Matiychuk Mykola D. Obushak Andrzej Gzella Yuri V. Ostapiuk 《Tetrahedron letters》2008,49(31):4648-4651
Various novel 3,5a,6,11b-tetrahydro-2H,5H-chromeno[4′,3′:4,5]thiopyrano[2,3-d][1,3]thiazol-2-ones were synthesized in 60-80% yields via domino-Knoevenagel-hetero-Diels-Alder reactions of 4-thioxo-1,3-thiazolidin-2-one with 3,7-dimethyl-6-octenal, 2-allyloxybenzaldehydes and 2-formylphenyl (E)-3-aryl-2-propenoates with base catalysis. The possibility of stereo- and regioselective cycloaddition was investigated. 相似文献
84.
Andriy O. Bryhas Vasyl S. Matiychuk Tadeusz Lis Vasyl Kinzhybalo Victor V. Smalius Mykola D. Obushak 《Tetrahedron letters》2013
A new, catalyst-free, domino Knoevenagel–hetero-Diels–Alder elimination oxidation reaction is reported. 5-Aryl-2H,6H-chromeno[4′,3′:4,5]thiopyrano[2,3-d][1,3]thiazol-2-ones are formed in moderate to good yields via reaction of 2-(3-aryl-3-chloro-2-propenyloxy)benzaldehydes with 4-thioxo-1,3-thiazolidin-2-one. 相似文献
85.
Shalimov Aleksandr A. Kolotylo Mykola V. Babiy Lyubov V. Muzychka Oksana V. Onys’ko Petro P. Rozhkov Vladimir V. 《Chemistry of Heterocyclic Compounds》2018,54(11):1033-1039
Chemistry of Heterocyclic Compounds - A convenient methodology for the synthesis of previously unreported (1H-indol-6-yl)phosphonic acid derivatives has been described. Reaction of... 相似文献
86.
87.
Composition-nominative logics (CNL) are program-oriented logics. They are based on algebras of partial predicates which do not have fixed arity. The aim of this work is to present CNL as institutions. Homomorphisms of first-order CNL are introduced, satisfaction condition is proved. Relations with institutions for classical first-order logic are considered. Directions for further investigation are outlined. 相似文献
88.
89.
A new, simple, one-step synthesis of 3-substituted 3,4-dihydroisocoumarins is developed. The products are obtained by the reaction of o-methoxycarbonyl arenediazonium bromides with unsaturated compounds in the presence of CuBr as a catalyst. 相似文献
90.
Mykola Tkach Julia Seti Oxana Voitsekhivska Vasyl Gutiv Evgenia Vereshko 《Molecular Crystals and Liquid Crystals》2020,701(1):48-58
AbstractThe quantum theory of renormalized energy spectrum of the system of localized two-level quasiparticle, with degenerated spectrum, interacting with polarization phonons, being the model of multilayered nanostructure, is developed within the modified Feynman-Pines diagram technique. Effectively taking into account the multi-phonon processes, the theory is valid in a wide range of energies which contains the main states and the satellite groups of energies produced by the resonant bound-to-phonons states of quasiparticle in the vicinity of the threshold energies of their radiation. The properties of renormalized spectrum of the system are analyzed and dependences of the widths of groups of energy levels (main and satellite) on the magnitudes of inter-level coupling constants are obtained. 相似文献