排序方式: 共有27条查询结果,搜索用时 15 毫秒
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MR Eskildsen AB Abrahamsen PL Gammel DJ Bishop NH Andersen K Mortensen PC Canfield 《Pramana》2002,58(5-6):903-905
We compare the results of small angle neutron scattering on the flux line lattice (FLL) obtained in the borocarbide superconductor
LuNi2B2C with the applied field along the c- and a-axes. For H‖c the temperature dependence of the FLL structural phase transition from square to hexagonal symmetry was investigated. Above
10 K the transition onset field. H
2(T), rises sharply, bending away from H
c2(T) in contradiction to theoretical predictions of the two merging. For H‖a a first order FLL reorientation transition is observed at H
tr=3–3.5 kOe. Below H
tr the FLL nearest neighbor direction is parallel to the b-axis, and above H
tr to the c-axis. This transition cannot be explained using nonlocal corrections to the London model. 相似文献
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We demonstrate 10-fs pulses from a diode-pumped, soft-aperture Kerr lens mode-locked Cr3+:LiCAF laser with a spectral bandwidth of 150 nm and 40 mW of output power at a repetition rate of 110 MHz. For dispersion compensation, double-chirped mirrors and prisms are used. The pulses are characterized by use of spectral shearing interferometry. 相似文献
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Johannes Soellner Mario Tenne Dr. Gerhard Wagenblast Prof. Dr. Thomas Strassner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(29):9914-9918
The synthesis and characterization of eight unprecedented phosphorescent C^C* cyclometalated mesoionic aryl‐1,2,3‐triazolylidene platinum(II) complexes with different β‐diketonate ligands are reported. All compounds proved to be strongly emissive at room temperature in poly(methyl methacrylate) films with an emitter concentration of 2 wt %. The observed photoluminescence properties were strongly dependent on the substitution on the aryl system and the β‐diketonate ligand. Compared to acetylacetonate, the β‐diketonates with aromatic substituents (mesityl and duryl) were found to significantly enhance the quantum yield while simultaneously reducing the emission lifetimes. Characterization was carried out by standard techniques, as well as solid‐state structure determination, which confirmed the binding mode of the carbene ligand. DFT calculations, carried out to predict the emission wavelength with maximum intensity, were in excellent agreement with the (later) obtained experimental data. 相似文献
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Hendrik Leopold Dr. Mario Tenne Dr. Alexander Tronnier Dr. Stefan Metz Dr. Ingo Münster Dr. Gerhard Wagenblast Prof. Dr. Thomas Strassner 《Angewandte Chemie (International ed. in English)》2016,55(51):15779-15782
Binuclear C^C* cyclometalated NHC platinum(II) compounds with bridging amidinate ligands were synthesized to evaluate their photophysical properties. Their three‐dimensional structures were determined by a combination of 2D NMR experiments, mass spectrometry, DFT calculations, and solid‐state structure analysis. The bridging amidinate ligands enforce short distances between the platinum centers of the two cyclometalated structures, which gives rise to extraordinary photophysical properties. 相似文献