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41.
A. V. Ankudinov M. S. Dunaevskii V. A. Marushchak A. N. Titkov S. V. Ivanov S. V. Sorokin T. V. Shubina P. S. Kop’ev A. Waag G. Landwehr 《Physics of the Solid State》2000,42(10):1927-1934
The atomic-force microscopy is used for studying the effect of atmospheric conditions on the morphology of (001) growth surfaces and (110) cleavage planes of layers in II–VI compounds with a high ZnSe content. It is proved directly for the first time that the formation of nanoclusters on these surfaces is accompanied by corrosion of the entire surface due to the accumulation of corrosion products. The corrosion of the surface attains saturation even at a depth of a few (2–3) monolayers, which constrains the total volume of nanoclusters on the surface. A further increase in the size of nanoclusters with time occurs due to a decrease in their number. The corrosion depth can locally increase significantly in the surface regions with considerable internal stresses; in particular, corrosion can evolve deep inside the stressed interfaces in instrumental structures. 相似文献
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Kristina F. Baranova Aleksei A. Titov Alexander F. Smolyakov Andrey Yu. Chernyadyev Oleg A. Filippov Elena S. Shubina 《Molecules (Basel, Switzerland)》2021,26(22)
A series of emissive Cu(I) cationic complexes with 3-(2-pyridyl)-5-phenyl-pyrazole and various phosphines: dppbz (1), Xantphos (2), DPEPhos (3), PPh3 (4), and BINAP (5) were designed and characterized. Complexes obtained exhibit bright yellow-green emission (ca. 520–650 nm) in the solid state with a wide range of QYs (1–78%) and lifetimes (19–119 µs) at 298 K. The photoluminescence efficiency dramatically depends on the phosphine ligand type. The theoretical calculations of buried volumes and excited states explained the emission behavior for 1–5 as well as their lifetimes. The bulky and rigid phosphines promote emission efficiency through the stabilization of singlet and triplet excited states. 相似文献
44.
N. A. Ustynyuk T. V. Filatova V. N. Vinogradova L. I. Leont'eva O. V. Semeikin L. M. Epshtein E. S. Shubina L. N. Saitkulova E. V. Bakhmutova A. L. Chistyakov I. V. Stankevich 《Russian Chemical Bulletin》1999,48(6):1165-1173
The main regularities of the reactions of 1-haloalkynes RC≡CX with carbonylmetallate anions [(η5-C5R′5)(CO)3M]− (R′ = H (1–3),, M=Cr (1), M=Mo (2), or M=W (3); R′ =Me (4–6), M=Cr (4), M=Mo (5), or M=W (6) were revealed. It was established that the first stage of the reactions of anions1–6 with bromo- or iodoalkynes RC≡CX (X=Br or I) involved the transfer of the halogen atom from the sp-hybridized carbon atom
to the transition metal atom to form carbonyl halides [(η5-C5R′5)(CO)3MX. To the contrary, the reactions of anions1–6 with chloroalkynes RC≡CCl proceeded selectively as a nucleophilic substitution at the unsaturated carbon atom, the reaction
rate being governed by the nucleophilicity of the carbonylmetallate anions and the electron-withdrawing ability of the R group.
These reaction paths are consistent with the structures of the lowest unoccupied molecular orbitals (LUMO) in the PhC≡CX molecules
(X=Cl, Br, or I) calculated by the MNDO/PM3 method. In the case of the reactions of 1-chloroheptyne-1 C1C≡CC5H11
n, anions1–3 appeared to be insufficiently nucleophilic, but these reactions can be performed as cross-coupling of the carbonylmetallate
anions with chloroalkynes catalyzed by palladium complexes.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1176–1184, June, 1999. 相似文献
45.
Lyakhova E. G. Fedorov S. N. Shubina L. K. Radchenko O. S. Kalinovsky A. I. Dvitrenok P. S. Stonik V. A. 《Russian Chemical Bulletin》2003,52(4):1022-1026
The structures of products obtained by reductive debromination and CF3COOH- and KOH-induced transformations of natural chamigrane-type sesquiterpenoid (6S,10R)-10-bromo-3,11,11-trimethyl-7-methylidenespiro[5,5]undec-2-en-4-one (dactylone) isolated from the sea hare Aplysia dactylomela were analyzed. The absolute configurations of the reaction products were established by CD spectra taking into account the configuration of the starting dactylone. 相似文献
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A new sterol — 24 ethyl-25-methylcholesta-5,22-dien-3-ol — has been isolated by column chromatography on silica gel from extracts of the spongeHalichondria sp. Its structure has been established on the basis of an analysis of GLC-MS results and of PMR and13C NMR spectroscopy and has been confirmed by ozonolysis.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 464–467, August–September, 1984. 相似文献
49.
Natalia V. Belkova Elena S. Shubina Evgenii I. Gutsul Lina M. Epstein Igor L. Eremenko Sergei E. Nefedov 《Journal of organometallic chemistry》2000,610(1-2)
The interaction of rhenium hydrides ReHX(CO)(NO)(PR3)2 1 (X=H, R=Me (a), Et (b), iPr (c); X=Cl, R=Me (d)) with a series of proton donors (indole, phenols, fluorinated alcohols, trifluoroacetic acid) was studied by variable temperature IR spectroscopy. The conditions governing the hydrogen bonding ReHHX in solution and in the solid state (IR, X-ray) were elucidated. Spectroscopic and thermodynamic characteristics (−ΔH=2.3–6.1 kcal mol−1) of these hydrogen bonded complexes were obtained. IR spectral evidence that hydrogen bonding with hydride atom precedes proton transfer and the dihydrogen complex formation was found. Hydrogen bonded complex of ReH2(CO)(NO)(PMe3)2 with indole (2a–indole) and organyloxy-complex ReH(OC6H4NO2)(CO)(NO)(PMe3)2 (5a) were characterized by single-crystal X-ray diffraction. A short NHHRe (1.79(5) Å) distance was found in the 2a–indole complex, where the indole molecule lies in the plane of the Re(NO)(CO) fragment (with dihedral angle between the planes 0.01°). 相似文献
50.
Galimov A. I. Rakhlin M. V. Klimko G. V. Zadiranov Yu. M. Guseva Yu. A. Troshkov S. I. Shubina T. V. Toropov A. A. 《JETP Letters》2021,113(4):252-258
JETP Letters - The characteristics of single photons emitted by columnar microstructures based on epitaxial microcavity heterostructures with distributed Bragg reflectors, which include... 相似文献