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Aakash D. Nidhankar Goudappagouda Divya S. Mohana Kumari Shailendra Kumar Chaubey Rashmi Nayak Rajesh G. Gonnade G. V. Pavan Kumar Retheesh Krishnan Sukumaran Santhosh Babu 《Angewandte Chemie (International ed. in English)》2020,59(31):13079-13085
Room‐temperature phosphorescence of metal and heavy atom‐free organic molecules has emerged as an area of great potential in recent years. A rational design played a critical role in controlling the molecular ordering to impart efficient intersystem crossing and stabilize the triplet state to achieve room‐temperature ultralong phosphorescence. However, in most cases, the strategies to strengthen phosphorescence efficiency have resulted in a reduced lifetime, and the available nearly degenerate singlet‐triplet energy levels impart a natural competition between delayed fluorescence and phosphorescence, with the former one having the advantage. Herein, an organic helical assembly supports the exhibition of an ultralong phosphorescence lifetime. In contrary to other molecules, 3,6‐phenylmethanone functionalized 9‐hexylcarbazole exhibits a remarkable improvement in phosphorescence lifetime (>4.1 s) and quantum yield (11 %) owing to an efficient molecular packing in the crystal state. A right‐handed helical molecular array act as a trap and exhibits triplet exciton migration to support the exceptionally longer phosphorescence lifetime. 相似文献
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J. J. Barroso K. G. Kostov J. P. Leite Neto 《International Journal of Infrared and Millimeter Waves》2001,22(2):265-276
With application to centimeter-wave monotron oscillators, the present work proposes a rippled wall cylindrical cavity that provides efficient coupling to a coaxial output circuit. Driven by a centered, solid 50 A, 34 keV electron beam, the corrugated cavity thus designed operates at 10.5 GHz in the 2-mode with two radial variations. The monotron operation is examined through 2.5D particle-in-cell simulation giving 260 kW average power output. This corresponds to 15.3 percent overall efficiency at the theoretical limit of 20.0% percent electronic effciency as predicted by one-dimensional analysis. 相似文献
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含氟聚酰亚胺光波导120 nm宽带耦合器的抗温度变动设计 总被引:1,自引:0,他引:1
提出一种适合于宽带光波导耦合器的抗温度变动的优化设计理论和方法。使用该理论和方法 ,在 1490~16 10nm带域上 ,对含氟聚酰亚胺光波导做了宽带光波导 3dB耦合器的抗温度变动设计。器件经三维波束传播法模拟运行验证 ,结果表明 ,在 12 0nm带宽上 ,从零下 10℃至零上 40℃的温度变动中 ,器件实现了 ( 0 .5 0 0± 0 .0 0 7)功率输出比的良好特性。同时报道了含氟聚酰亚胺薄膜波导的制备工艺及其温度特性和色散特性的测试。 相似文献