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991.
The pharmaceutical industry is reliant on a constant supply of new chemical entities and molecular targets for disease intervention. In this tutorial review, we want to illustrate that basic research studies on the biological function of natural products involved in plant-pathogen interactions can serve as an inspiring source for the identification of new bioactive entities as well as of strategies on how to achieve small molecule manipulation of biological systems. An application of findings from plant-pathogen interaction studies might therefore display a significant impact on drug discovery. 相似文献
992.
Louis A. Florence Edward C. Kinzel Robert L. Olmon James C. Ginn Markus B. Raschke Glenn D. Boreman 《Infrared Physics & Technology》2012,55(6):449-453
Tapered slot antennas (TSAs) consist of a planar non-resonant structure which couples incident radiation to a propagating waveguide mode. They are commonly used at microwave and radio frequencies because they are fundamentally broadband and have small profiles. Because of their planar layout and broadband response they have recently been scaled to infrared frequencies where they have advantages for sensing and energy harvesting. We use scattering-type scanning near-field optical microscopy (s-SNOM) to study the mode transformation of two types of TSA operating in the thermal infrared (λ0 = 10.6 μm) with respect to electric field amplitude and phase. The results agree well with simulation showing both the phase reversal across the tapered slot and the traveling of wave fronts along the tapered slot, yet they also reveal high sensitivity of device performance to inhomogeneities in the geometry or illumination. This study will aid future design and analysis of practical non-resonant antennas operating at optical and infrared frequencies. 相似文献
993.
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
994.
Pelegrina-Bonilla G Hausmann K Liu K Sayinc H Morgner U Neumann J Kracht D 《Optics letters》2012,37(11):1844-1846
We developed a fused fiber coupler (FFC) capable of multiplexing wavelengths in the range of 795 nm and 2 μm. A simple 2D simulation model to calculate the pretaper length for matching the propagation constants in the coupling region was established. Based on the numerical data, we fabricated an asymmetric FFC consisting of two different fibers with single-mode guidance for the respective wavelength, achieving a transmission of 90% in the signal fiber for both wavelengths. In order to demonstrate the application, we integrated the FFC into a core pumped thulium-doped fiber amplifier. 相似文献
995.
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
996.
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
997.
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
998.
Dirk Mortag Thomas Theeg Katharina Hausmann Lars Grüner-Nielsen Kim Giessmann Jespersen Uwe Morgner Dieter Wandt Dietmar Kracht Jörg Neumann 《Optics Communications》2012,285(5):706-709
An all-fiber-integrated linear chirped-pulse amplifier system generating microjoule pulse energies is reported. It is seeded by an all-fiber dissipative-soliton laser and incorporates a newly developed fiber stretcher, whose dispersive properties match that of the grating compressor. Pulse durations of 189 fs with energies of 2.2 μJ were achieved after compression. The average power was 9.8 W at the repetition rate of 4.5 MHz. 相似文献
999.
1000.
Qiang Zhao Tim‐Patrick Fellinger Markus Antonietti Jiayin Yuan 《Macromolecular rapid communications》2012,33(13):1149-1153
Layer‐by‐layer (LbL) assembly technique is applied for the first time for the preparation of nitrogen‐doped carbon capsules. This approach uses colloid silica as template and two polymeric deposition components, that is, poly(ammonium acrylate) and a poly (ionic liquid) poly(3‐cyanomethyl‐1‐vinylimidazolium bromide), which acts as both the carbon precursor and nitrogen source. Nitrogen‐doped carbon capsules are prepared successfully by polymer wrapping, subsequent carbonization and template removal. The as‐synthesized carbon capsules contain ≈7 wt% of nitrogen and have a structured specific surface area of 423 m2 g−1. Their application as supercapacitor has been briefly introduced. This work proves that LbL assembly methodology is available for preparing carbon structures of complex morphology. 相似文献