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41.
M. Yu. Sinev Z. T. Fattakhova V. Yu. Bychkov V. I. Lomonosov Yu. A. Gordienko 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2018,92(3):424-429
The dynamics of oxygen uptake by mixed Ce0.55Pr0.45O2–x oxide is studied in a pulsed oxygen supply mode using in situ high-temperature heat flow differential scanning calorimetry. It is stated that the oxidation proceeds in two regimes: a fast one at the beginning of the oxidation process, and a slow one, which is controlled by the diffusion of oxygen through the bulk of the solid at the later stages of the process. Analysis of the shape of calorimetric profiles reveals some processes, accompanied by heat release, that occur in the sample in the absence of oxygen in the gas phase. These could be due to both the redistribution of consumed oxygen in the oxide lattice and the lattice relaxation associated with the transformation of phases with different arrangements of oxygen vacancies in them. The heat effect (which diminishes from ~60 to ~40 kJ/mol in the course of oxygen uptake) associated with the oxidation of the reduced form of mixed Ce–Pr oxide, corresponds to the oxidation of praseodymium ions from (3+) to (4+). 相似文献
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Dong‐Sik Shin Jungmok You Ali Rahimian Tam Vu Christian Siltanen Arshia Ehsanipour Gulnaz Stybayeva Julie Sutcliffe Alexander Revzin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(31):8360-8363
Cells may be captured and released using a photodegradable hydrogel (photogel) functionalized with antibodies. Photogel substrates were used to first isolate human CD4 or CD8 T‐cells from a heterogeneous cell suspension and then to release desired cells or groups of cells by UV‐induced photodegradation. Flow cytometry analysis of the retrieved cells revealed approximately 95 % purity of CD4 and CD8 T‐cells, suggesting that this substrate had excellent specificity. To demonstrate the possibility of sorting cells according to their function, photogel substrates that were functionalized with anti‐CD4 and anti‐TNF‐α antibodies were prepared. Single cells captured and stimulated on such substrates were identified by the fluorescence “halo” after immunofluorescent staining and could be retrieved by site‐specific exposure to UV light through a microscope objective. Overall, it was demonstrated that functional photodegradable hydrogels enable the capture, analysis, and sorting of live cells. 相似文献
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Odinets I. L. Vereshchagina Ya. A. Artyushin O. I. Kalyanova R. M. Mastryukova T. A. Ishmaeva E. A. Fattakhova G. R. Chachkov D. V. Yarkova E. G. 《Russian Chemical Bulletin》2003,52(3):638-646
Under conditions of the phase transfer catalysis, acylation of (thio)phosphorylacetonitriles by (het)aroyl chlorides affords the Z-enol forms of C-acylation products in high yields. Their configurations were studied by IR spectroscopy, dipole moment measurements, and ab initio quantum-chemical calculations [B3LYP/6-31G(d)]. The C=C double bond and the phosphoryl or thiophosphoryl group have an s-cis arrangement. The possibility of strong intramolecular hydrogen bonding in these conformers is the governing factor responsible for the three-dimensional structures of the compounds under investigation. Derivatives of nicotinic acid existing in the individual form as zwitterions are the only exceptions. 相似文献
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Ishmaeva E. A. Vereshchagina Ya. A. Yarkova E. G. Burnaeva L. M. Litvinov I. A. Krivolapov D. B. Gubaidullin A. T. Mironov V. F. Fattakhova G. R. 《Russian Journal of General Chemistry》2002,72(8):1195-1201
2-X-5,6-benzo-1,3,2-dioxaphosphinin-4-ones (X = N = C = O, Cl, NEt2), regardless of their aggregative state, prefer one and the same conformation (flattened
sofa); the exocyclic substituent occupies either an axial (N = C = O, NEt2) or an equatorial (Cl) position. 相似文献
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V. M. Berestovitskaya N. I. Aboskalova E. A. Ishmaeva S. V. Bakhareva G. A. Berkova Ya. A. Vereshchagina A. V. Fel'gendler G. R. Fattakhova 《Russian Journal of General Chemistry》2001,71(12):1942-1949
A one-stage synthesis of 1-acyl-1-nitro-2-furyl(thienyl)ethenes was developed and structural assessment of the products was performed by means of 1H, IR, and UV spectroscopy and dipole moment measurements. The acetyl derivatives have Z configuration, and the benzoyl derivatives, E configuration. The UV and IR spectra, as well as the rather high dipole moments ( 5-6 D) point to an essential contribution in the structures of dipolar forms. 相似文献
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Alina Khaybullina Gulnaz Akhtaryanova Regina Mingazova Debasish Saha Ramil Izmailov 《International Journal of Theoretical Physics》2014,53(5):1590-1600
We investigate the stability regions of the thin-shells obtained by gluing the exterior Schwarzschild vacuum with two distinct classes of Ellis wormholes, one with zero and the other with nonzero total mass. Using the new concepts of thin-shell “mass” and of “external force” discovered recently by Garcia, Lobo and Visser, we shall apply their method to the explicit cases where some of the energy conditions in the bulk (on two sides) are violated. The stability regions are analyzed and the energetics is briefly discussed. Remarkably, we find that the stability zones are quite similar although the classes of Ellis wormholes are different. By the present examples, we confirm that the stability zones indicated by the force constraint (involving Φ and its derivatives) are more complete but restrictive than those from the mass constraint (not involving Φ). 相似文献