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101.
Blanzat M Turrin CO Perez E Rico-Lattes I Caminade AM Majoral JP 《Chemical communications (Cambridge, England)》2002,(17):1864-1865
We report the synthesis and the supramolecular auto-assembly of catanionic phosphorus-containing dendrimers mimicking multisite analogs of galactosylceramide. 相似文献
102.
Large-eddy simulation of low-frequency unsteadiness in a turbulent shock-induced separation bubble 总被引:2,自引:0,他引:2
The need for better understanding of the low-frequency unsteadiness observed in shock wave/turbulent boundary layer interactions
has been driving research in this area for several decades. We present here a large-eddy simulation investigation of the interaction
between an impinging oblique shock and a Mach 2.3 turbulent boundary layer. Contrary to past large-eddy simulation investigations
on shock/turbulent boundary layer interactions, we have used an inflow technique which does not introduce any energetically
significant low frequencies into the domain, hence avoiding possible interference with the shock/boundary layer interaction
system. The large-eddy simulation has been run for much longer times than previous computational studies making a Fourier
analysis of the low frequency possible. The broadband and energetic low-frequency component found in the interaction is in
excellent agreement with the experimental findings. Furthermore, a linear stability analysis of the mean flow was performed
and a stationary unstable global mode was found. The long-run large-eddy simulation data were analyzed and a phase change
in the wall pressure fluctuations was related to the global-mode structure, leading to a possible driving mechanism for the
observed low-frequency motions.
相似文献
103.
A wide range of diffractive elements have been used to evaluate the topological charge of Laguerre–Gaussian beams. Here, we show theoretically and experimentally that this charge can be simply and readily measured from the interference pattern in Young’s double-slit experiment. It can be evaluated from the twisting order of the interference. The results are confronted with previously published studies. The potentialities of the method are then compared with existing techniques. 相似文献
104.
Advanced photoresist technologies by intricate molecular brush architectures: Diblock brush terpolymer-based positive-tone photoresist materials
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105.
Manuela Bartolini Marina Naldi Dan V. Nicolau Falco C. M. J. M. van Delft Jeroen van Zijl Jaap Snijder Eric F. C. van den Heuvel Emile P. Naburgh Natalia Calonghi Vincenza Andrisano 《Analytical and bioanalytical chemistry》2013,405(2-3):795-804
Human acetylcholinesterase (AChE) is a widely studied target enzyme in drug discovery for Alzheimer’s disease (AD). In this paper we report evaluation of the optimum structure and chemistry of the supporting material for a new AChE-based fluorescence sensing surface. To achieve this objective, multilayered silicon wafers with spatially controlled geometry and chemical diversity were fabricated. Specifically, silicon wafers with silicon oxide patterns (SiO2/Si wafers), platinum-coated silicon wafers with SiO2 patterns (SiO2/Pt/Ti/Si wafers), and Pt-coated wafers coated with different thicknesses of TiO2 and SiO2 (SiO2/TiO2/Pt/Ti/Si wafers) were labelled with the fluorescent conjugation agent HiLyte Fluor 555. Selection of a suitable material and the optimum pattern thickness required to maximize the fluorescence signal and maintain chemical stability was performed by confocal laser-scanning microscopy (CLSM). Results showed that the highest signal-to-background ratio was always obtained on wafers with 100 nm thick SiO2 features. Hence, these wafers were selected for covalent binding of human AChE. Batch-wise kinetic studies revealed that enzyme activity was retained after immobilization. Combined use of atomic-force microscopy and CLSM revealed that AChE was homogeneously and selectively distributed on the SiO2 microstructures at a suitable distance from the reflective surface. In the optimum design, efficient fluorescence emission was obtained from the AChE-based biosensing surface after labelling with propidium, a selective fluorescent probe of the peripheral binding site of AChE. Figure
Micropatterned silicon wafers containing covalently bound human acetylcholinesterase. The binding and displacement of the fluorescent probe propidium (red areas) from the enzyme's peripheral binding site is visualized by scanning laser microscopy 相似文献
106.
We report on the deformation of an air-water surface with a totally reflected low-power laser beam, inducing a convex mirror effect on the beam propagation. This bending is stronger close to the critical angle and depends on the polarization of the laser light. A model, leading to a simple dependence between the Goos-H?nchen shift and the radius of curvature of the interface, supports these observations. Bendings with radius of curvature as low as 0.10 m are demonstrated. 相似文献
107.
England J Guo Y Van Heuvelen KM Cranswick MA Rohde GT Bominaar EL Münck E Que L 《Journal of the American Chemical Society》2011,133(31):11880-11883
The trigonal-bipyramidal high-spin (S = 2) oxoiron(IV) complex [Fe(IV)(O)(TMG(2)dien)(CH(3)CN)](2+) (7) was synthesized and spectroscopically characterized. Substitution of the CH(3)CN ligand by anions, demonstrated here for X = N(3)(-) and Cl(-), yielded additional S = 2 oxoiron(IV) complexes of general formulation [Fe(IV)(O)(TMG(2)dien)(X)](+) (7-X). The reduced steric bulk of 7 relative to the published S = 2 complex [Fe(IV)(O)(TMG(3)tren)](2+) (2) was reflected by enhanced rates of intermolecular substrate oxidation. 相似文献
108.
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