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901.
Santos M Roy BC Goicoechea H Campiglia AD Mallik S 《Journal of the American Chemical Society》2004,126(34):10738-10745
We present a promising approach to protein sensing based on Eu3+ ions incorporated into polymerized liposomes. The sensitization of Eu3+ is accomplished with 5-aminosalicylic acid, which provides energy transfer for a stable reference signal and a wide wavelength excitation range free from protein interference. The lipophilic character of polymerized liposomes provides the appropriate platform for protein interaction with the lanthanide ion. Quantitative analysis is based on the linear relationship between the luminescence signal of Eu3+ and protein concentration. Because no spectral shift of the lanthanide luminescence is observed upon protein interaction, qualitative analysis is based on the luminescence lifetime of polymerized liposomes. This parameter, which changes significantly upon protein-liposome interaction, follows a well-behaved single-exponential decay that might be useful for protein identification. 相似文献
902.
Porrès L Mongin O Katan C Charlot M Pons T Mertz J Blanchard-Desce M 《Organic letters》2004,6(1):47-50
[structure: see text] Novel octupolar fluorophores derived from the symmetrical functionalization of a triphenylamine core with strong acceptor peripheral groups via phenylene-ethynylene linkers have been synthesized and shown to exhibit high fluorescence quantum yields, very large TPA cross-sections in the red-NIR region, and suitable photostability. 相似文献
903.
Grégory?BerhuyEmail author Marina?Monsurrò Jean-Pierre?Tignol 《Mathematische Zeitschrift》2004,248(2):313-323
Using a cohomological obstruction, we construct examples of absolutely simple adjoint classical groups of type 2An with n3mod4, Cn or 1Dn with n0mod4, which are not R-trivial hence not stably rational.Mathematics Subject Classification (2000): 11E57, 20G15in final form: 13 June 2003 相似文献
904.
905.
Cocchi M Manfredini M Marchetti A Pigani L Seeber R Tassi L Ulrici A Vignali M Zanardi C Zannini P 《Annali di chimica》2002,92(3):187-201
Measurements of the refractive index n for the binary mixtures 2-chloroethanol + 2-methoxyethanol in the 0 < or = t/degree C < or = 70 temperature range have been carried out with the purpose of checking the capability of empirical models to express physical quantity as a function of temperature and volume fraction, both separately and together, i.e., in a two independent variables expression. Furthermore, the experimental data have been used to calculate excess properties such as the excess refractive index, the excess molar refraction, and the excess Kirkwood parameter delta g over the whole composition range. The quantities obtained have been discussed and interpreted in terms of the type and nature of the specific intermolecular interactions between the components. 相似文献
906.
A simple and robust solid-phase extraction (SPE) procedure for the cleanup and sample preconcentration of antifungals (ketoconazole, clotrimazole, itraconazole, fluconazole, and voriconazole) and their metabolites after incubation with human liver microsomes, as well as a simplified capillary zone electrophoresis (CZE) method for their rapid analysis, have been developed to determine the stability of these compounds in in vitro samples. Three different sample pretreatment procedures using SPE with reversed-phase sorbents (100 mg C8, 100 mg C18, and 30 mg Oasis-HLB) were studied. The highest and most reproducible recoveries were obtained using a 30 mg Oasis-HLB sorbent and methanol containing 2% acetic acid as eluent. Enrichment by a factor of about four times was achieved by reconstituting the final SPE eluates to a small volume. For the CZE separation, good separations without interfering peaks due to the in vitro matrix were obtained with a simple running electrolyte using a fused-silica capillary. The best separation for all components originated by each tested drug after incubation with human liver microsomes (unmetabolized parent drug and its metabolites) was obtained using a 0.05 M phosphate running buffer (pH 2.2) without additives. The effect of the injection volume was also investigated in order to obtain the best sensitivity. Performance levels in terms of precision, linearity, limits of detection, and robustness were determined. 相似文献
907.
S. V. Tarasenko 《Journal of Experimental and Theoretical Physics》2001,92(2):326-337
The singularities in the spectrum of bulk acoustic phonons polarized in the sagittal plane are investigated on a plate made of a uniaxial ferroelastic material undergoing a proper ferroelastic transition from the paraelectric to the ferroelectric phase. The singularities are induced by anomalies in the reflection of this type of normal elastic vibrations at the crystal boundary. 相似文献
908.
Elisa Martinelli Valentina Domenici Marina Ragnoli Norbert Moszner Giancarlo Galli 《Macromolecular Symposia》2006,234(1):139-146
We prepared a novel fluorinated polymer from a bicycloacrylate monomer, (1H,1H,2H,2H)-perfluorododecyl 2-(bicyclo[3.1.0]hex-1-yl)acrylate, by radical ring opening polymerization. The bulk properties of the polymer were investigated by thermal analysis and X-ray diffraction, which proved the existence of a smectic mesophase up to the isotropization temperature of 74 °C. Furthermore, a solid state NMR study was started to characterize domains with different mobility mainly by 13C cross-polarization magic angle spinning and T2 selective experiments. We found that the polymer is a homogeneous sample with the presence of dynamic motions in the kHz regime below the glass transition temperature. 相似文献
909.
Nada Kouti‐Hulita Aleksandar Danilovski Miroslav Maleevi Marina Orei Miljenko Dumi 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1144-1145
The 2,8‐dihydroxy‐1,3,7,9‐tetramethyl‐6,12‐dihydrodipyrido[1,2‐a:1′,2′‐d]pyrazinediylium dication possesses 2/m symmetry and lies in the mirror plane together with a chloride anion and the water O atom. The dication also lies on an inversion centre, i.e. C16H20N2O22+·2Cl?·2H2O. Due to these symmetry constrictions the dication adopts an unexpected planar conformation. Molecules are linked by O—H?O and O—H?Cl hydrogen bonds to form chains, which are cross‐connected by C—H?Cl attractive interactions forming a complex three‐dimensional hydrogen‐bond network. 相似文献
910.
María Galiana-Cameo Marina Borraz Yaroslava Zelenkova Dr. Vincenzo Passarelli Prof. Fernando J. Lahoz Prof. Jesús J. Pérez-Torrente Prof. Luis A. Oro Dr. Andrea Di Giuseppe Dr. Ricardo Castarlenas 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(43):9598-9608
A series of Rh(κ2-BHetA)(η2-coe)(IPr) complexes bearing 1,3-bis-hetereoatomic acidato ligands (BHetA) including carboxylato (O,O), thioacetato (O,S), amidato (O,N), thioamidato (N,S), and amidinato (N,N), have been prepared by reaction of the dinuclear precursor [Rh(μ-Cl)(IPr)(η2-coe)]2 with the corresponding anionic BHetA species. The RhI-NHC-BHetA compounds catalyze the dimerization of aryl alkynes, showing excellent selectivity for the head-to-tail enynes. Among them, the acetanilidato-based catalyst has shown an outstanding catalytic performance reaching unprecedented TOF levels of 2500 h−1 with complete selectivity for the gem-isomer. Investigation of the reaction mechanism supports a non-oxidative pathway in which the BHetA ligand behaves as proton shuttle through intermediate κ1-HBHetA species. However, in the presence of pyridine as additive, the identification of the common RhIIIH(C≡CPh)2(IPr)(py)2 intermediate gives support for an alternative oxidative route. 相似文献