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61.
62.
Dr. Lenka Štacková Marina Russo Dr. Lucie Muchová Vojtěch Orel Prof. Libor Vítek Dr. Peter Štacko Prof. Petr Klán 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(58):13184-13190
Carbon monoxide (CO) is an endogenous signaling molecule that controls a number of physiological processes. To circumvent the inherent toxicity of CO, light-activated CO-releasing molecules (photoCORMs) have emerged as an alternative for its administration. However, their wider application requires photoactivation using biologically benign visible and near-infrared (NIR) light. In this work, a strategy to access such photoCORMs by fusing two CO-releasing flavonol moieties with a NIR-absorbing cyanine dye is presented. These hybrids liberate two molecules of CO in high chemical yields upon activation with NIR light up to 820 nm and exhibit excellent uncaging cross-sections, which surpass the state-of-the-art by two orders of magnitude. Furthermore, the biocompatibility and applicability of the system in vitro and in vivo are demonstrated, and a mechanism of CO release is proposed. It is hoped that this strategy will stimulate the discovery of new classes of photoCORMs and accelerate the translation of CO-based phototherapy into practice. 相似文献
63.
64.
Effect of Cold Atmospheric Pressure Plasma on Maize Seeds: Enhancement of Seedlings Growth and Surface Microorganisms Inactivation 总被引:1,自引:0,他引:1
Anna Zahoranová Lucia Hoppanová Juliana Šimončicová Zlata Tučeková Veronika Medvecká Daniela Hudecová Barbora Kaliňáková Dušan Kováčik Mirko Černák 《Plasma Chemistry and Plasma Processing》2018,38(5):969-988
Cold atmospheric pressure ambient air plasma generated by Diffuse Coplanar Surface Barrier Discharge (DCSBD) was investigated for inhibition of native microbiota and potentially dangerous pathogens (Aspergillus flavus, Alternaria alternata and Fusarium culmorum) on the maize surface. Moreover, the improvement of germination and growth parameters of maize seeds was evaluated. Maize (Zea mays L.; cv. Ronaldinio), one of the most important cultivated crops worldwide, was selected as the research material. Electrical measurements confirmed the high volume power density (80 W cm?3) of DCSBD plasma. Non-equilibrium plasma state evaluated using optical emission spectroscopy showed values of vibrational and rotational temperature (2700?±?300) K and (370?±?75) K, respectively. Changes on the plasma treated seeds surface were studied by water contact angle measurement, scanning electron microscope analysis and Fourier transform infrared spectroscopy. A complete devitalisation of native microbiota on the surface of seeds was observed after a short treatment time of 60 s (bacteria) and 180 s (filamentous fungi). The plasma treatment efficiency of artificially contaminated maize seeds was estimated as a reduction of 3.79 log (CFU/g) in F. culmorum after a 60-s plasma treatment, 4.21 log (CFU/g) in A. flavus and 3.22 log (CFU/g) in A. alternata after a 300-s plasma treatment. Moreover, the obtained results show an increase in wettability, resulting in a better water uptake and in an enhancement of growth parameters. The investigated DCSBD plasma source provides significant technical advantages and application potential for seed surface finishing without the use of hazardous chemicals. 相似文献
65.
Libor Dostál Roman Jambor Robert Jirásko Jaroslav Hole?ek 《Journal of fluorine chemistry》2008,129(3):167-172
The organoantimony(III) difluorides containing Y,C,Y-chelating, so called pincer, ligands ([2,6-(YCH2)2C6H3]SbF2; Y = MeO, t-BuO and Me2N) were prepared by the reaction of corresponding dichlorides ([2,6-(YCH2)2C6H3]SbCl2; Y = MeO, t-BuO and Me2N) with two equivalents of organotin(IV) fluorinating agents Me3SnF or 2-(Me2NCH2)C6H4Sn(n-Bu2)F, respectively. The structure of organonantimony fluorides was determined both in solution by 1H, 13C and 19F NMR spectroscopy and in the solid state using X-ray diffraction. 相似文献
66.
Rostislav Černý Stefan Funken Evgueni Spodarev 《Methodology and Computing in Applied Probability》2008,10(1):23-37
The Boolean model of Wiener sausages is a random closed set that can be thought of as a random collection of parallel neighborhoods
of independent Wiener paths in space. It describes e.g. the target detection area of a network of sensors moving according
to the Brownian dynamics whose initial locations are chosen in the medium at random. In the paper, the capacity functional
of this Boolean model is given. Moreover, the one- and two-point coverage probabilities as well as the contact distribution
function and the specific surface area are studied. In and , the one- and two-point coverage probabilities are calculated numerically by Monte Carlo simulations and as a solution of
the heat conduction problem. The corresponding approximation formulae are given and the error of approximation is analyzed.
Research supported by the grant GACR 201/06/0302. 相似文献
67.
Emanuele Casini Enrico Miglierina Łukasz Piasecki Libor Veselý 《Israel Journal of Mathematics》2016,216(1):355-369
We present a Lindenstrauss space with an extreme point that does not contain a subspace linearly isometric to c. This example disproves a result stated by Zippin in a paper published in 1969 and it shows that some classical characterizations of polyhedral Lindenstrauss spaces, based on Zippin’s result, are false, whereas some others remain unproven; then we provide a correct proof for those characterizations. Finally, we also disprove a characterization of polyhedral Lindenstrauss spaces given by Lazar, in terms of the compact norm-preserving extension of compact operators, and we give an equivalent condition for a Banach space X to satisfy this property. 相似文献
68.
Amorphous iron(III) oxide--a review 总被引:1,自引:0,他引:1
69.
Plasma-polymerized films of vinyltriethoxysilane were surface characterized using the sessile drop technique. The surface
free energy and its components were evaluated using the Owens-Wendt-Kaelble geometric mean method, Wu harmonic mean method,
and van Oss, Chaudhury, and Good acid-base theory. Influence of deposition conditions on the surface free energy was demonstrated
in the study. Improved wettability of the films was related to the diminished concentration of apolar methyl groups in plasma
polymers. An increased concentration of carbonyl and hydroxyl groups resulted in a very small improvement of the polar component. 相似文献
70.
Tanja Soldatović Predrag Čanović Radivoje Nikolić Ratomir Jelić Živadin D. Bugarčić 《Journal of solution chemistry》2009,38(1):57-71
The formation equilibria of the [Pt(SMC)(H2O)2]+ complex with some biologically relevant ligands such as L-methionine (L-met) and glutathione (GSH) were studied. The stoichiometry
and stability constants of the formed complexes are reported, and the concentration distribution of the various complex species
has been evaluated as a function of pH. The reaction between [PtCl2(SMC)] and guanosine-5′-monophosphate (5′-GMP) was studied by 1H NMR spectroscopy. The NMR spectra indicated that first step is the hydrolysis of the [PtCl2(SMC)] complex and second step is the substitution of an aqua ligand, either in the cis or trans position with guanosine-5′-monophosphate in molar ratio 1:1. The values of rate constant showed faster substitution of coordinated
H2O in the trans position to the S donor atom of S-methyl-L-cysteine, whereas the slower reaction was assigned to the displacement of the
cis coordinated aqua molecule. This is due to the strong trans labilization effect of coordinated sulfur.
Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users. 相似文献