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排序方式: 共有250条查询结果,搜索用时 15 毫秒
141.
142.
Maitane Salsamendi Jose Abad Rebeca Marcilla Cristina Pozo‐Gonzalo Antonio Urbina Hans Grande Jaime Colchero David Mecerreyes 《先进技术聚合物》2011,22(12):1665-1672
This paper describes a new strategy to obtain PEDOT/Au‐nanorods nanocomposites with different PEDOT: Au ratio. A polymeric ionic liquid (PIL) was used as stabilizer during the chemical synthesis of PEDOT dispersions. PEDOT/Au‐nanorods dispersions in organic media were obtained. Electrochemical characterization of PEDOT/Au‐nanorods nanocomposites revealed that the addition of Au nanorods modified the electroactivity of the conducting films by reducing the oxidation potential from +0.33 to +0.23 V (versus Ag/AgCl). Optical contrast (ΔT%) of the films decreased from 17% for neat PEDOT films to 8% for PEDOT/Au‐nanorods nanocomposites films (3:1 (v/v)) while switching times (from 1 to 4 sec) were similar to neat PEDOT. Conductivity of the films increased from 0.027 S/cm for neat PEDOT to 0.691 S/cm for PEDOT/Au‐nanorods nanocomposites. Nanoscale morphology and contact potential of PEDOT/Au‐nanorods nanocomposites were investigated in detail by Scanning Force Microscopy. Electrical measurements show a clear contact potential difference between the ITO substrate and the PEDOT/Au‐nanorods film. On the film, no contact potential inhomogeneity is observed indicating that the Au‐nanorods are uniformly dispersed in the film. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
143.
Khan A Khan MI Iqbal Z Shah Y Ahmad L Nazir S Watson DG Khan JA Nasir F Khan A Ismail 《Talanta》2011,84(3):789-801
A new, simple, economical and validated high-performance liquid chromatography linked with electrochemical detector (HPLC-ECD) method has been developed and optimized for different experimental parameters to analyze the most common monothiols and disulfide (cystine, cysteine, homocysteine, methionine, reduced (GSH) and oxidized glutathione (GSSG)) and ascorbic acid present in human plasma and erythrocytes using dopamine as internal standard (IS). Complete separation of all the targets analytes and IS at 35 °C on Discovery HS C18 RP column (250 mm × 4.6 mm, 5 μm) was achieved using 0.05% TFA:methanol (97:3, v/v) as a mobile phase pumped at the rate of 0.6 ml min−1 using electrochemical detector in DC mode at the detector potential of 900 mV. The limits of detection (3 S/N) and limits of quantification (10 S/N) of the studied compounds were evaluated using dilution method. The proposed method was validated according to standard guidelines and optimization of various experimental parameters and chromatographic conditions was carried out. The optimized and validated HPLC-ECD method was successfully applied for the determination of the abovementioned compounds in human plasma and erythrocytes. The method will be quite suitable for the determination of plasma and erythrocyte profile of ascorbic acid and aminothiols in oxidative stress and other basic research studies. 相似文献
144.
We analyze the benzene/Au(111) interface taking into account charging energy effects to properly describe the electronic structure of the interface and van der Waals interactions to obtain the adsorption energy and geometry. We also analyze the interface dipoles and discuss the barrier formation as a function of the metal work-function. We interpret our DFT calculations within the induced density of interface states (IDIS) model. Our results compare well with experimental and other theoretical results, showing that the dipole formation of these interfaces is due to the charge transfer between the metal and benzene, as described in the IDIS model. 相似文献
145.
Gismeros Moreno Raúl Corral Abad Eduardo Meneses Alonso Jesús Gómez García María Jesús Castejón Sisamón Cristina 《Nonlinear dynamics》2022,107(3):1859-1886
Nonlinear Dynamics - Smooth approaches are able to model reasonably well contact/impact events between two bodies, showing some peculiarities when dealing with certain geometries and arising... 相似文献
146.
Diastereodifferentiation of novel naphthalene dyads by fluorescence quenching and excimer formation.
Sergio Abad Ignacio Vayá M Consuelo Jiménez Uwe Pischel Miguel A Miranda 《Chemphyschem》2006,7(10):2175-2183
Four new bichromophoric naphthalene dyads in form of diastereomeric pairs are synthesized and photophysically characterized. For a closely related group of compounds (NAP-NAP, MNAP-NAP, MNAP-MNAP), systematic variation of the urea linker led to the observation of intramolecular fluorescence quenching for tertiary urea, but not for secondary urea. Chiral information contained in the dyads has an impact on the efficiency of this process. Furthermore, for the case of (R,R)-MNAP-MNAP, excimer formation in the pre-organized dyad was noted, while being absent in the corresponding (R,S) diastereomer. These differences in photophysical behavior are ascribed to the geometry of the linker and to the chiral information contained in the diastereomeric compounds. Other dyads, such as NPX-NPX, included naproxen as the chromophore. For these compounds strong excimer emission is obtained, however, only very small diastereodifferentiation is observed for the two investigated stereoisomers. 相似文献
147.
Rahmati Ali Abad M. Shayesteh S. Farjami Shayesteh H. Farjami 《Physics of the Solid State》2020,62(1):120-130
Physics of the Solid State - TiO2 nanoparticles were synthesized via the hydrothermal method. As-synthesized TiO2 properties were characterized by XRD, EDX, FESEM, FTIR, and UV-Vis spectroscopy.... 相似文献
148.
The exact solution for the two-particle spectrum of the Heisenberg-Peierls one-dimensional spin chain is given by working in the fermionic representation. The resulting equations for the eigenvalues are, in some sense, similar to those of the BCS model and must be solved numerically. 相似文献
149.
150.
J. Navarro-Laboulais F. López J. I. Torregrosa S. C. Cardona A. Abad 《Journal of mathematical chemistry》2007,42(4):969-990
Experimental respirometry shows oxygen uptake rate (OUR) transients which are not predicted by standard ASM models. These
transients were analysed from a detailed modelling of hybrid respirometers. Structural identifiability analysis of several
models based on local isomorphism transformation approach is carried out. It can be concluded that the knowledge of the OUR
does not help positively on an accurate determination of biokinetic parameters. The measure of dissolved oxygen (DO) is just
enough to calculate the group of identifiable parameters from the models in a calibration process. The analysis suggests to
use only the DO data to avoid the systematic errors associated to OUR calculations. Furthermore, the existence of OUR transients
after a precise modelling of the hybrid respirometer is deduced. The duration of these transients are the result of the coupling
between the kinetics of the biological process and the residence time in the respiration chamber of the instrument. An expression
for the duration of these transients is proposed. 相似文献