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11.
Exploring the Effect of Ligand Structural Isomerism in Langmuir–Blodgett Films of Chiral Luminescent EuIII Self‐Assemblies
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Agostino Galanti Dr. Oxana Kotova Dr. Salvador Blasco Chloe J. Johnson Dr. Robert D. Peacock Shaun Mills Prof. John J. Boland Prof. Martin Albrecht Prof. Thorfinnur Gunnlaugsson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(28):9709-9723
Here we have investigated the influence of the antenna group position on both the formation of chiral amphiphilic EuIII‐based self‐assemblies in CH3CN solution and, on the ability to form monolayers on the surface of quartz substrates using the Langmuir–Blodgett technique, by changing from the 1‐naphthyl ( 2(R) , 2(S) ) to the 2‐naphthyl ( 1(R) , 1(S) ) position. The evaluation of binding constants of the self‐ assemblies in CH3CN solution was achieved using conventional techniques such as UV/Visible and luminescence spectroscopies along with more specific circular dichroism (CD) spectroscopy. The binding constants obtained for EuL , EuL2 and EuL3 species in the case of 2‐naphthyl derivatives were comparable to those obtained for 1‐naphthyl derivatives. The analysis of the changes in the CD spectra of 1(R) and 1(S) upon addition of EuIII not only allowed us to evaluate the values of the binding constants but the resulting recalculated spectra may also be used as fingerprints for assignment of the chiral self‐assembly species formed in solution. The obtained monolayers were predominantly formed from EuL3 (≈85 %) with the minor species present in ≈15 % EuL2 . 相似文献
12.
13.
V. P. Zakharov O. N. Makurina E. V. Timchenko P. E. Timchenko I. A. Bratchenko S. P. Kotova 《Bulletin of the Lebedev Physics Institute》2010,37(7):222-226
The results of the study of spectral characteristics of tree crops of Samara city as a method for measuring air pollutant
concentrations. Even-age plantings of European white birch at ten points of Samara near main motorways were chosen as objects
of study. It was shown that the ratio K of the light backscattering intensities at wavelengths of 750 and 550 nm is sensitive to pollutants and insensitive to measurement
conditions. The relation between the coefficient K and the leaf chlorophyll concentration and their dependence on the total concentration of anthropogenic substances characteristic
of internal-combustion engine exhausts (CO, NO2, SO2) were experimentally determined. The carbon oxide concentration has the strongest effect on the coefficient K. This makes it possible to apply the described method tested by the example of Samara city to ecological mapping of city
territories. 相似文献
14.
Adsorption of α-tocopherol from ethanol solution on clinoptilolite tuff activated with 4.0 M HCl is studied. α-Tocopherol adsorption isotherm is analyzed using the Langmuir, Freundlich, and Redlich-Peterson adsorption theories. The adsorption of α-tocopherol from dilute solutions on this sorbent is ascertained to be described by the Langmuir model. 相似文献
15.
A. K. Chernyshov S. P. Kotova V. L. Velichanskii 《Journal of Russian Laser Research》2002,23(2):132-147
It is shown that the type of lateral waveguide of a laser diode cannot be determined uniquely based on just the measured magnitude of astigmatism. For a unique determination, the K-factor of Petermann, which characterizes the wavefront curvature at the laser output facet, must be measured as well. In order to determine the type of lateral waveguide, a setup for measuring astigmatic distances in the range 0–200 m with an error of ±2 m and a K-factor with an error of 20% was developed. Operational features of the setup were analyzed, and a technique that allows one to minimize the effect of beam ellipticity on the measurement results was found. Using the technique, the optimization of spatial matching of a laser diode with a ring interferometer of the butterfly type was accomplished. For transformation of the astigmatic elliptical beam into the axially symmetric mode of the interferometer, we have used an optical system that consists of two cylindrical and one spherical lenses. The algorithm for designing the matching system was developed, and the 85% injection of radiation of a AlGaAs laser diode into the principal mode of a ring interferometer was experimentally demonstrated. 相似文献
16.
Solovieva A Vstovsky G Kotova S Glagolev N Zav'yalov BS Belyaev V Erina N Timashev P 《Micron (Oxford, England : 1993)》2005,36(6):508-518
This work is to show that activity of porphyrins in singlet oxygen generation (SOG) is determined not only by their molecular structure but also by supramolecular structure of porphyrin containing systems. This is demonstrated by results of studies of SOG in the gas phase by vacuum deposited tetraphenylporphyrin (TPP) layers under photoexcitation conditions. The structure of the layers was studied by atomic force microscopy (AFM), TEM in diffraction regime (TED) and by the flicker-noise spectroscopy (FNS) method. It was shown that substrates affect the deposited layers structure only at earlier stages of the layer formation. AFM and TED data, together with FNS quantitative parameters of TPP layers, show directly that the chemical activity of solid-phase systems can be determined not only by their chemical nature but also by their supramolecular structure. 相似文献
17.
Natalya V. Kul''kova Valentina G. Kotova Marina Yu. Kvyatkovskaya Dmitry Yu. Murzin 《Reaction Kinetics and Catalysis Letters》2000,69(1):95-104
Influence of metal ions on hydrogen peroxide decomposition on the liquid-phase ammoximation of cyclohexanone was studied in homogeneous and heterogeneous (over titanium silicalite) conditions. The latter reaction is accompanied by side reactions, which deactivate the catalyst. Deactivation behavior is discussed. 相似文献
18.
N. V. Tverdova G. V. Girichev S. A. Shlykov V. V. Rybkin O. V. Kotova N. P. Kuz’mina 《Russian Journal of Inorganic Chemistry》2010,55(3):421-426
A mass spectrometric study of the overheated vapor over the nickel(II), copper(II), and zinc(II) N,N′-ethylenebis(salicylaldiminato) complexes between 300 and 865°C has been carried out. Throughout this temperature range,
the overheated vapor over all of the complexes contains no ions heavier than the molecular ion [MO2N2C16H14]+. At ∼600°C, Cu(salen) and Zn(salen) interact with the structural material of the double-chamber two-temperature effusion
cell (Kh18N10T steel). The complexes are thermally very stable. The fragmentation pattern of the chelates under electron-impact
ionization is metal-dependent. 相似文献
19.
G. V. Girichev N. V. Tverdova N. P. Kuz’mina A. O. Simakov O. V. Kotova 《Russian Journal of Inorganic Chemistry》2009,54(12):1975-1980
A mass spectrometric study of the overheated vapor over the complexes Ni(acacen), Cu(acacen), and Zn(acacen) (H2acacen = N,N′-ethylenebis(acetylacetonimine)) has been carried out in the temperature range of 180–760°C. Irrespective of the degree of
overheating, the vapor phases over all of these compounds contain no ions heavier than the molecular ion [MO2N2C12H18]+. The existence of molecular ions in the overheated vapor in the double-chamber two-temperature effusion cell is evidence
of the high thermal stability of the complexes. The onset temperature of the thermal decomposition of Ni(acacen), Cu(acacen),
and Zn(acacen) is 690, 610, and 560°C, respectively. The way of fragmentation of the chelates under electron impact ionization
depends on the nature of the metal. 相似文献
20.
A. G. Vendilo H. Rönkkömáki N. N. Kotova M. Hannu-Kuure N. E. Kovaleva L. H. J. Lajunen 《Russian Journal of Inorganic Chemistry》2010,55(10):1559-1562
The complexation of strontium with triisopropyl ester of dichloromethylene-bis(phosphonic acid) (NaL) is examined using 31P NMR in water and the hydrophilic ionic liquid 1-butyl-3-methylimidazolium dicyanamide ([BMIM][N(CN)2]):
相似文献