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131.
Ramón Martínez-Máñez Félix Sancenón Mandy Hecht Mustafa Biyikal Knut Rurack 《Analytical and bioanalytical chemistry》2011,399(1):55-74
This review highlights how the combination of supramolecular principles and nanoscopic solid structures enables the design
of new hybrid sensing ensembles with improved sensitivity and/or selectivity and for the targeting of analytes for which selectivity
is hard to achieve by conventional methods. Such ideas are bridging the gap between molecules, materials sciences and nanotechnology.
Relevant examples will be detailed, taking into account functional aspects such as (1) enhanced coordination of functionalized
solids, (2) enhanced signalling through preorganization, (3) signalling by assembly–disassembly of nanoscopic objects, (4)
biomimetic probes utilizing discrimination by polarity and size and (5) distinct switching and gating protocols. These strategies
are opening new prospects for sensor research and signalling paradigms at the frontier between nanotechnology, smart materials
and supramolecular chemistry. 相似文献
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136.
Mustafa Barri George K. El Khoury Helge I. Andersson Bjrnar Pettersen 《国际流体数值方法杂志》2010,64(7):777-792
Direct numerical simulation (DNS) has been performed to study the channel flow over a backward‐facing step at a Reynolds number Reb=5600 based on the step height h and the inflow bulk velocity Ub. A dynamic method has been used in order to generate realistic turbulent inflow conditions. The results upstream of the step compared well with the fully developed channel flow. Downstream of the step our results show excellent agreement with experimental data. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
137.
The next-nearest-neighbour (NNN) effect in tetranuclear iron(II) complexes of thiacalixarene macrocycles using the isotropic
Heisenberg model has been investigated in order to understand its effects on the observed plateau of magnetization. Although
NNN effect is generally very weak in these kinds of systems, it was calculated that its response is quite significant to the
external perturbations in certain temperature regions. Using the isotropic Heisenberg exchange Hamiltonian, zero-field energy
spectra have been calculated for this particular tetranuclear system. The average magnetic moments with and without next-nearest-neighbour
interactions were also calculated. In order to verify the calculations, the results were compared with experimental data taken
from the literature, whence, it is suggested that observed magnetic behaviour can be improved by taking into account the NNN
effect. 相似文献
138.
Yavuz Surme Ibrahim Narin Mustafa Soylak Huseyin Yuruk Mehmet Dogan 《Mikrochimica acta》2007,157(3-4):193-199
The conditions for cloud point extraction of lead(II) from aqueous solutions were investigated and optimized. The procedure
is based on the separation of Pb(II) – brillant cresyl blue (BCB) complexes into the micellar media by adding the surfactant
Triton X-114. After phase separation, the surfactant-rich phase was dissolved with 1 mol L−1 HNO3 in ethanol and diluted with 1 mol L−1 HNO3 solution before lead was determined by flame atomic absorption spectrometry. Optimization of the pH, ligand and surfactant
quantities, incubation time, temperature, viscosity, sample volume, and interfering ions was performed. The effects of the
matrix ions were also examined. The detection limits for three times the standard deviations of the blank for lead were 7.5 μg L−1 for water samples and 0.33 μg g−1 for sediment samples. The validity of cloud point extraction was checked by employing certified reference samples of Lake
Sediment IAEA-SL-1 and Sewage Sludge BCR-CRM 144R. The procedure was applied to natural waters and sediment samples with satisfactory
results (recoveries >95%, relative standard deviations <6.4%). 相似文献
139.
Nair VA Mustafa SM Mohler ML Fisher SJ Dalton JT Miller DD 《Tetrahedron letters》2004,45(51):9475-9477
A series of optically active nonsteroidal selective androgen receptor modulators with structures analogous to bicalutamide was prepared by replacing the trifluoromethyl group with iodine and the sulfonyl linker by oxygen. 相似文献
140.
Certain Cu(I) and Cu(II) salts are able to mediate the dimerization of arylboronic acids in DMF. They provide the corresponding symmetrical biaryls in moderate to very good yields. It is possible to run the reaction catalytically under an oxygen atmosphere without a significant loss of yields. 相似文献