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371.
Ya. V. Baklanova I. Yu. Arapova I. R. Shein L. G. Maksimova K. N. Mikhalev T. A. Denisova 《Journal of Structural Chemistry》2013,54(1):111-118
A comparative analysis of 6,7Li NMR spectra is performed for the samples of monoclinic lithium titanate obtained at different synthesis temperatures. In the 7Li NMR spectra three lines are found, which differ in quadrupole splitting frequencies v Q and according to ab initio EFG calculations are assigned to three crystallographic sites of lithium: Li1 (v Q ~ 27 kHz); Li2 (v Q ~ 59 kHz); Li3 (v Q ~ 6 kHz). The dynamics of lithium ions is studied in a wide temperature range from 300 K to 900 K. It is found that the narrowing of 7Li NMR spectra as a result of thermally activated diffusion of lithium ions in the low-temperature Li2TiO3 sample is observed at a higher temperature in comparison with a sample of high-temperature lithium titanate. Based on the analysis of 6Li NMR spectra it is assumed that there is mixed occupancy of lithium and titanium sites in the corresponding layers of the crystal structure of low-temperature lithium titanate, which hinders lithium ion transfer over regular crystallographic sites. 相似文献
372.
O. S. Kudryashova K. A. Bortnik E. Yu. Chukhlantseva S. A. Denisova A. E. Lesnov 《Russian Journal of Inorganic Chemistry》2013,58(2):250-252
Solubility in ternary aqueous stratifying systems containing Catamine AB (alkylbenzyldimethylammonium chloride [C n H2n + 1N+(CH3)2CH2C6H5] · Cl, a cationic surfactant, where n = 10–18) and LiCl, NaCl, KCl, and NH4Cl inorganic salts was studied for the first time at 25°C. The boundaries of two-phase liquid equilibrium fields were determined. The studied stratifying systems were proposed for use in the liquid extraction of metal ions. 相似文献
373.
I. R. Shein T. A. Denisova Ya. V. Baklanova A. L. Ivanovskii 《Journal of Structural Chemistry》2011,52(6):1043-1050
Within density functional theory by an ab initio molecular dynamics method (SIESTA code) the features of structural, electronic properties and chemical bonding in lithium
metallates Li2MO3 (M = Ti, Zr, Sn) are studied, as well as of their protonated forms Li2−x
H
x
MO3 at all possible H+ → Li+ substitutions. With the use of the calculated crystal orbital overlap populations and the formation energies of Li2−x
H
x
MO3 the most preferred H+ → Li+ substitutions in Li2MO3 metallates are discussed. 相似文献
374.
Ya. V. Baklanova L. G. Maksimova N. A. Zhuravlev V. Ya. Kavun T. A. Denisova 《Bulletin of the Russian Academy of Sciences: Physics》2010,74(8):1097-1099
Li2TiO3 and H2TiO3 samples with various degrees of dispersion were investigated by X-ray diffraction, NMR spectroscopy, and electronic microscopy.
It was shown that H2TiO3 has a distinct structure and exhibits high sorption activity in relation to rare earth elements. The sorption activity of
H2TiO3 grows due to the increase in specific surface of samples. 相似文献
375.
V. M. Denisov L. T. Denisova L. A. Irtyugo V. S. Biront 《Physics of the Solid State》2010,52(7):1362-1365
The heat capacity, thermal conductivity, thermal diffusivity, and thermal expansion of Bi4Ge3O12 single crystals have been measured over a wide temperature range. 相似文献
376.
The resonance characteristics (inhomogeneous FMR linewidth ΔH) in highly dispersed (d=0.1–3 μm) powders of crystalline and amorphous Co-P alloys are investigated as a function of the composition, particle size, and
atomic structure. It is established that ΔH for powders of amorphous Co-P alloys is two to three times larger than ΔH for crystalline Co-P powders. According to the investigations performed, this is caused by thermodynamically stimulated segregation
of nonmagnetic Co2P inclusions, apparently an effective relaxation channel, in the amorphous state of Co-P powders.
Fiz. Tverd. Tela (St. Petersburg) 41, 464–467 (March 1999) 相似文献
377.
Inga R. Grin Grigory V. Mechetin Rustem D. Kasymov Evgeniia A. Diatlova Anna V. Yudkina Sergei N. Shchelkunov Irina P. Gileva Alexandra A. Denisova Grigoriy A. Stepanov Ghermes G. Chilov Dmitry O. Zharkov 《Molecules (Basel, Switzerland)》2021,26(21)
Uracil–DNA glycosylases are enzymes that excise uracil bases appearing in DNA as a result of cytosine deamination or accidental dUMP incorporation from the dUTP pool. The activity of Family 1 uracil–DNA glycosylase (UNG) activity limits the efficiency of antimetabolite drugs and is essential for virulence in some bacterial and viral infections. Thus, UNG is regarded as a promising target for antitumor, antiviral, antibacterial, and antiprotozoal drugs. Most UNG inhibitors presently developed are based on the uracil base linked to various substituents, yet new pharmacophores are wanted to target a wide range of UNGs. We have conducted virtual screening of a 1,027,767-ligand library and biochemically screened the best hits for the inhibitory activity against human and vaccinia virus UNG enzymes. Although even the best inhibitors had IC50 ≥ 100 μM, they were highly enriched in a common fragment, tetrahydro-2,4,6-trioxopyrimidinylidene (PyO3). In silico, PyO3 preferably docked into the enzyme’s active site, and in kinetic experiments, the inhibition was better consistent with the competitive mechanism. The toxicity of two best inhibitors for human cells was independent of the presence of methotrexate, which is consistent with the hypothesis that dUMP in genomic DNA is less toxic for the cell than strand breaks arising from the massive removal of uracil. We conclude that PyO3 may be a novel pharmacophore with the potential for development into UNG-targeting agents. 相似文献
378.
379.
Vladlen P. Zhukov Veronika M. Zainullina Vladimir G. Zubkov Alexander P. Tyutyunnik Tatiana A. Denisova 《ChemInform》2001,32(41):no-no
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
380.