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991.
Ultrastrong coupling is studied in a modulation-doped parabolic potential well coupled to an inductance-capacitance resonant circuit. In this system, in accordance to Kohn's theorem, strong reduction of the energy level separation caused by the electron-electron interaction compensates the depolarization shift. As a result, a very large ratio of 27% of the Rabi frequency to the center resonance frequency as well as a polariton gap of width 2π × 670 GHz are observed, suggesting parabolic quantum wells as the system of choice in order to explore the ultrastrong coupling regime. 相似文献
992.
993.
Florian Bruckner Christoph Vogler Michael Feischl Dirk Praetorius Bernhard Bergmair Thomas Huber Markus Fuger Dieter Suess 《Journal of magnetism and magnetic materials》2012
3D magnetostatic Maxwell equations are solved using the direct Johnson–Nédélec FEM–BEM coupling method and a reduced scalar potential approach. The occurring BEM matrices are calculated analytically and approximated by H-matrices using the ACA+ algorithm. In addition a proper preconditioning method is suggested that allows to solve large-scale problems using iterative solvers. 相似文献
994.
Hamacek J Poggiali D Zebret S El Aroussi B Schneider MW Mastalerz M 《Chemical communications (Cambridge, England)》2012,48(9):1281-1283
A new tripodal ligand has been designed by connecting pyridine-based coordination units to a rigid triptycene moiety. Its reaction with europium(III) provides three-dimensional tetranuclear edifices, whose structural and photophysical characteristics as well as host-guest interactions are discussed in this contribution. 相似文献
995.
Jiang L Yan Y Drechsler M Huang J 《Chemical communications (Cambridge, England)》2012,48(59):7347-7349
We present here a host-guest approach to construct enzyme-triggered assembly systems on the basis of surfactant-cyclodextrin complexes and α-amylase. We realized enzyme-responsive model self-assembly systems including monolayers, micelles, and vesicles. The host-guest approach is expected to be extended to more complicated assembly systems with widespread applications. 相似文献
996.
Cruz H Fanselow M Holbrey JD Seddon KR 《Chemical communications (Cambridge, England)》2012,48(45):5620-5622
Using in situ viscosity measurement, the rate of cellulose dissolution in a number of ionic liquids has been determined allowing their performance as solvents to be quantitatively assessed. 1-Butyl-3-methylimidazolium ethanoate was shown to dissolve cellulose faster than analogous ionic liquids with chloride or dimethylphosphate anions. Analysis of the data highlights the influence of both anion basicity and relative concentration on the rate of dissolution. 相似文献
997.
Grammel M Dossa PD Taylor-Salmon E Hang HC 《Chemical communications (Cambridge, England)》2012,48(10):1473-1474
Orthogonal amino acid reporters allow the selective labeling of different cell types in heterogeneous populations through the expression of engineered aminoacyl tRNA synthetases. Here, we demonstrate that para-ethynylphenylalanine (PEP) can be used as an orthogonal amino acid reporter for efficient selective labeling of an intracellular bacterial pathogen during infection. 相似文献
998.
999.
Two different hexaarylbenzenes with three pyrene and three triarylamine substituents in different positions (trigonal symmetric and asymmetric arrangement) were synthesized, and their charge-transfer states were investigated by optical spectroscopy. In these multichromophoric systems triarylamine acts as the electron donor and pyrene as the electron acceptor. A reference chromophore with only one donor-acceptor pair was also investigated. All these chromophores form charge-transfer states upon photoexcitation which relax with a moderate fluorescence quantum yield to the ground state. The compounds do not differ significantly concerning most of their fluorescence properties, which shows that the fluorescent charge-transfer state is very similar in all chromophores. This observation indicates symmetry breaking for the symmetric chromophore within fluorescence lifetime of several tens of ns. This interpretation was substantiated by fluorescence excitation anisotropy measurements in a sucrose octaacetate matrix. 相似文献
1000.