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61.
Marek Bučko Danica Mislovičová Jozef Nahálka Alica Vikartovská Jana Šefčovičová Jaroslav Katrlík Ján Tkáč Peter Gemeiner Igor Lacík Vladimír Štefuca Milan Polakovič Michal Rosenberg Martin Rebroš Daniela Šmogrovičová Juraj Švitel 《Chemical Papers》2012,66(11):983-998
Biological molecules such as enzymes, cells, antibodies, lectins, peptide aptamers, and cellular components in an immobilized form are extensively used in biotechnology, in biorecognition and in many medicinal applications. This review provides a comprehensive summary of the developments in new immobilization materials, techniques, and their practical applications previously developed by the authors. A detailed overview of several immobilization materials and technologies is given here, including bead cellulose, encapsulation in ionotropic gels and polyelectrolyte complexes, and various immobilization protocols applied onto surfaces. In addition, the review summarises the screening and design of an immobilization protocol, practical applications of immobilized biocatalysts in the industrial production of metabolites, monitoring, and control of fermentation processes, preparation of electrochemical/optical biosensors and biofuel cells. 相似文献
62.
G. R. Kosmambetova P. E. Strizhak É. M. Moroz T. E. Konstantinova A. V. Gural’skii V. P. Kol’ko V. I. Gritsenko I. A. Danilenko O. A. Gorban 《Theoretical and Experimental Chemistry》2007,43(2):102-107
The morphological and catalytic properties of samples of nanomeric zirconium dioxide, stabilized with yttrium oxide, manufactured
via the effect of a UHF field during the process of drying precipitated zirconium hydroxide and calcination at temperatures
from 300 to 1000 °C, were studied. It was shown that the highest activity in the oxidation of CO occurred with 40 nm particles
of zirconium dioxide prepared at 1000 °C.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 2, pp. 96–101, March–April, 2007. 相似文献
63.
N. K. Gusarova P. A. Volkov N. I. Ivanova N. A. Chernysheva S. V. Yas’ko A. I. Albanov B. A. Trofimov 《Russian Journal of General Chemistry》2010,80(8):1602-1608
Under the conditions of free-radical initiation (AIBN, UV irradiation), divinyl selenide regioselectively reacts with secondary
phosphine sulfides and phosphine selenides to afford, depending on the ratio of the reagents, mono- or diadducts mainly of
the anti-Markownikoff structure. The conditions which allow obtaining the diadducts in up to 97% yield are found. By the example
of 2-{[2-(diphenethylphosphoroselenoyl) ethyl]selanyl}ethyl(diphenethyl)phosphine selenide the diadducts were shown to react
with aqueous hydrogen peroxide at 53–56°C to give vinyl(diphenethyl)phosphine oxide in 76% yield. 相似文献
64.
The Becke3LYP density functional was used to study structural and thermodynamic parameters of bivalent zinc cation complexes
with selected substrates and ACE inhibitors (H2O/OH−, neutral forms of captopril, zofenoprilat, omapatrilat, CH3CONHCH3, and N-terminal anions of captopril, zofenoprilat, omapatrilat, enalaprilat, perindoprilat, trandolaprilat, and fosinoprilat). The
combination of DFT and the conductor-like polarizable continuum model (CPCM) were employed to compute the Gibbs interaction
energies (ΔG) between Zn2+ and the selected ACE inhibitors for dielectric media with ɛ = 5 (to simulate the protein environment) and for water media (ɛ = 78.39) for comparison purposes. The results show that ΔG is sensitive to the dielectric constant of the environment and that lower dielectric medium favors the binding of inhibitors
to the zinc cation. 相似文献
65.
T. N. Filippov P. A. Kolin’ko D. V. Kozlov E. M. Glebov V. P. Grivin V. F. Plyusnin 《Kinetics and Catalysis》2016,57(2):191-199
The photochemistry and photophysics of aqueous solutions of uranyl nitrate have been investigated by nanosecond laser photolysis with excitation at 266 and 355 nm and by time-resolved fluorescence spectroscopy. The quantum yield has been determined for (UO22+)* formation under excitation with λ = 266 and 355 nm light (φ = 0.35). The quantum yield of uranyl luminescence under the same conditions is 1 × 10–2 and 1.2 × 10–3, respectively, while the quantum yield of luminescence in the solid state is unity, irrespective of the excitation wavelength. The decay of (UO22+)* in the presence of ethanol is biexponential. The rate constants of this process at pH 3.4 are k1 = (2.7 ± 0.2) × 107 L mol–1 s–1 and k2 = (5.4 ± 0.2) × 106 L mol–1 s–1. This biexponential behavior is explained by the existence of different complex uranyl ion species in the solution. The addition of colloidal TiO2 to the solution exerts no effect on the quantum yield of (UO22+)* formation or on the rate of the reaction between (UO22+)* and ethanol. The results of this study have been compared with data available from the literature. 相似文献
66.
Wanli Nie Wenqing Xu Maxim V. Borzov Dmitrii P. Krut’ko Judith A.K. Howard 《Journal of organometallic chemistry》2008,693(13):2355-2368
The novel bidentate ligand, C5H4CPh2CH2-(1-Me-C3H4N2) (3), has been prepared and characterized as its lithium salt LiC5H4CPh2CH2-(1-Me-C3H4N2) (3-Li). Cyclopentadiene HC5H4CPh2CH2-(1-Me-C3H4N2) (3-H) has been obtained from 6,6-diphenylfulvene and 1,2-dimethylimidazoline (1). In THF-d8 solution in the presence of 1, (1-methylimidazoline-2-yl)methyllithium (2) has been proved to undergo gradual conversion into a dilithium derivative of N1-methyl-N2-[(1E,2E)-1-methyl-2-(1-methylimidazolidine-2-idene)ethylidene]ethane-1,2-diamine (2a). In a solution, cyclopentadiene 3-H has been shown to undergo isomerization into 3-{N-[2-(N-methylamino)ethyl]amino}-1,1-diphenyl-1,2-dihydropentalene (4) and, further, into a mixture of 4 and two rotameric 3-[N-(2-aminoethyl)-N-methylamino]-1,1-diphenyl-1,2-dihydropentalenes (5a) and (5b). Treatment of the lithium salt 3-Li with Me3SiCl has lead to 3-{N-[2-(N-trimethylsilylamino)ethyl]amino}-1,1-diphenyl-1,2-dihydropentalene (6) as the dominant component in the reaction mixture. In the latter case the expected Me3Si-C5H4CPh2CH2-(1-Me-C3H4N2) (3-Si) was not observed. Stannylation of 3-Li with 1 equiv. of Me3SnCl has resulted in formation of a mixture of Me3Sn-C5H4CPh2CH2-(1-Me-C3H4N2) (3-Sn), (Me3Sn)2-C5H3CPh2CH2-(1-Me-C3H4N2) (3-Sn2), and cyclopentadiene 3-H in a ca. 2:1:1 molar ratio. Monocyclopentadienyl complexes {[η5:η1-κN-C5H4CPh2CH2-(1-Me-C3H4N2)]MCl3 (M = Ti (7), Zr (8)) have been prepared starting from the organotin and organolithium compounds 3-Sn and 3-Li, respectively. The dynamic behavior of complexes 7 and 8 has been investigated by means of variable-temperature NMR spectroscopy in solutions. The molecular structures of the dihydropentalene 4, binuclear complex {[η5:η1-κN-C5H4CPh2CH2-(1-Me-C3H4N2)]ZrCl2}2(μ-Cl)28, and a coordination dimer of the dilithium salt 2a have been established by X-ray diffraction analysis. In the crystal structure of the 2a-dimer, the shortest known Li-Li contact has been found. 相似文献
67.
68.
Components of the Stokes vector are shown to undergo amplitude- and phase-frequency variations for a magneto-optical thin rod-shaped crystal located under conditions of magnetomechanical resonance when the variable magnetic field is directed at an acute angle to the light propagation axis coinciding with the crystal oscillation axis. It is noted that the phase relations for these components must be taken into account for polarized light when finding the connection between the variable and constant components of the Stokes vector. 相似文献
69.
Via the method of turbidity points, a fragment of the phase diagram of the polysulfone-poly(ethylene glycol) 400-dimethylacetamide three-component system was constructed. This system is a unique object with both an upper critical solution temperature and a second-order lower critical solution temperature. Viscosity characteristics and activation parameters of the viscous flow of concentrated and dilute polysulfone solutions in dimethylacetamide containing poly(ethylene glycol) were studied. An abnormal increase in the solution viscosity with temperature that precedes the phase transition was found. With the use of IR spectroscopy and the viscometry of dilute solutions, it was shown that it is possible to form additive compounds between the components in a solution. 相似文献
70.
The mechanism of interaction of trypsin with the sulfathiazole was studied through using fluorescence quenching and UV-visible absorption spectra at pH 7.4. The Stern-Volmer quenching constants, binding constants, number of binding sites and the corresponding thermodynamic parameters ΔHo, ΔSo and ΔGo were calculated at different temperatures. The effect of common metal ions on the constants was also discussed. The results suggest that sulfathiazole can interact strongly trypsin and that there is the formation of trypsin-sulfathiazole complex and the interaction can be explained on the basis of hydrogen bonds and van der Waals forces. The binding distance (r) between the donor (trypsin) and acceptor (sulfathiazole) was 3.52 nm based on the Förster’s non-radiative energy transfer theory. The detection and quantification limits of sulfathiazole were calculated as 2.52 and 8.40 μM in the presence of trypsin, respectively. The relative standard deviation (RSD) was 4.086 % for determinations (n?=?7) of a sulfathiazole solution with the concentration of 7.54 μM. 相似文献