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91.
A theory of concentration polarization of a thin electrical double layer (DL) on a spherical particle is developed for the regime of large Peclet numbers which is realized in strong electric fields. In this regime, the concentration field arising outside DL is estimated under influence of diffusion and convection. According to the theory developed, polarization of DL at large Peclet numbers causes a change in the Stern potential, the formation of a dipole moment and the long-range potential. The diffuse layer deviates strongly from spherical symmetry and electroneutrality, and the screen of the surface charge is provided not only by the diffuse atmosphere but also by the charge induced in the convective-diffusion layer. The effect of electric field on the induced charge gives rise to the additional electroosmotic slip, that was called "secondary electroosmosis". Thus, a nonlinear additional term for the Smoluchowski formula of electrophoretic velocity is based on the changes of zeta-potential and on the secondary electroosmotic slip. The comparison of theory with experimental results revealed considerable fitting. 相似文献
92.
Myers MC Witschi MA Larionova NV Franck JM Haynes RD Hara T Grajkowski A Appella DH 《Organic letters》2003,5(15):2695-2698
[structure: see text] A strategy to restrict the highly flexible backbone conformation of a peptide nucleic acid (PNA) by incorporation of a cyclopentane ring is proposed. An asymmetric synthesis of cyclopentane-modified PNA is reported, and its binding properties were determined. The cyclopentane ring leads to a significant improvement in the binding properties of the resulting PNA to DNA and RNA. 相似文献
93.
Dmitriy V. Maltsev Alexander A. Spasov Pavel M. Vassiliev Maria O. Skripka Mikhail V. Miroshnikov Andrey N. Kochetkov Nataliya V. Eliseeva Yuliya V. Lifanova Tatyana A. Kuzmenko Lyudmila N. Divaeva Anatolii S. Morkovnik 《Molecules (Basel, Switzerland)》2021,26(19)
A number of novel 2,3,4,5-tetrahydro[1,3]diazepino[1,2-a]benzimidazole derivatives 2 were obtained by alkylation mainly in the 1H-tautomeric form of 2,3,4,5-tetrahydro[1,3]diazepino[1,2-a]benzimidazole or its 8,9-dimethyl-substituted analog 4-chlorobenzyl bromide, 4-chloroacetic acid fluoroanilide, and 4-tert-butylphenacyl bromide in neutral medium. Compounds 3 were cyclized and synthesized earlier with 11-phenacyl-substituted diazepino[1,2-a]benzimidazoles upon heating in conc. HBr. The chemical structures of the compounds were clarified by using the 1H Nuclear Magnetic Resonance Spectroscopy (1H-NMR) technique. Anxiolytic properties were evaluated using the elevated plus maze (EPM) and open field (OF) tests. The analgesic effect of compounds was estimated with the tail flick (TF) and hot plate (HP) methods. Besides, possible the influence of the test compounds on motor activities of the animals was examined by the Grid, Wire, and Rotarod tests. Compounds 2d and 3b were the most active due to their prominent analgesic and anxiolytic potentials, respectively. The results of the performed in silico analysis showed that the high anxiolytic activity of compound 3b is explained by the combination of a pronounced interaction mainly with the benzodiazepine site of the GABAA receptor with a prominent interaction with both the specific and allosteric sites of the 5-HT2A receptor. 相似文献
94.
We study a particular case of the two-dimensional Steinhaus theorem, giving estimates of the possible distances between points
of the formkα andkα+β on the unit circle, through an approximation algorithm of β by the pointskα. This allows us to compute covering numbers (maximal measures of Rokhlin stacks having certain prescribed regularity properties)
for the symbolic dynamical systems associated to the rotation of argument α, acting on the partition of the circle by the
points 0, β. We can the compute topological and measure-theoretic covering numbers for exchange of three intervals; in this
way, we prove that every ergodic exchange of three intervals has simple spectrum and build a new class of three-interval exchanges
which are not of rank one. 相似文献
95.
Nataliya F. Lazareva Alexandr I. Albanov Bagrat A. Shainyan Erich Kleinpeter 《Tetrahedron》2012,68(4):1097-1104
A number of N-substituted 2,2-dimethyl-1,4,2-oxazasilinanes 1 were synthesized and studied by variable temperature dynamic 1H and 13C NMR spectroscopy, room temperature 15N NMR spectroscopy and theoretical calculations at the DFT and MP2 levels of theory. Both the preferred conformers were assigned and the barrier to the ring inversion of the saturated six-membered ring determined. From 1 the corresponding methyl iodide salts were produced, their structure studied by X-ray analysis and found to be in excellent agreement with the results of the theoretical calculations. 相似文献
96.
Babak Nikolay L. Shishkin Oleg V. Shishkina Svitlana V. Gella Ivan M. Musatov Vladimir I. Novikova Nataliya B. Lipson Victoria V. 《Structural chemistry》2016,27(1):295-303
Structural Chemistry - New series of chiral dopants for cholesteric liquid-crystal compositions were synthesized on the base of 2-substituted allobetuline derivatives, and their steric structure... 相似文献
97.
98.
Andriiko Alexander A. Shpak Arseniy Ye. Andriyko Yuriy O. García José R. Khainakov Sergei A. Vlasenko Nataliya Ye. 《Journal of Solid State Electrochemistry》2012,16(5):1993-1998
Journal of Solid State Electrochemistry - Products of thermal decomposition of lithium permanganate LiMnO4·3H2O, which are formed in temperature range 160–900&;nbsp;°C, have been... 相似文献
99.
100.
Svetlana L. Yefimova Irina Yu. Kurilchenko Tatyana N. Tkacheva Nataliya S. Kavok Igor N. Todor Nataliya Yu. Lukianova Vasyl F. Chekhun Yuriy V. Malyukin 《Journal of fluorescence》2014,24(2):403-409
We report the Förster resonance energy transfer (FRET)-labeling of liposomal vesicles as an effective approach to study in dynamics the interaction of liposomes with living cells of different types (rat hepatocytes, rat bone marrow, mouse fibroblast-like cells and human breast cancer cells) and cell organelles (hepatocyte nuclei). The in vitro experiments were performed using fluorescent microspectroscopic technique. Two fluorescent dyes (DiO as the energy donor and DiI as an acceptor) were preloaded in lipid bilayers of phosphatidylcholine liposomes that ensures the necessary distance between the dyes for effective FRET. The change in time of the donor and acceptor relative fluorescence intensities was used to visualize and trace the liposome-to-cell interaction. We show that FRET-labeling of liposome vesicles allows one to reveal the differences in efficiency and dynamics of these interactions, which are associated with composition, fluidity, and metabolic activity of cell plasma membranes. 相似文献