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[structure: see text] A short synthesis of the marine sponge metabolites slagenins A (1), B (2), and C (3) is described. The synthetic route features the preparation of beta-hydroxyimidazolone 4 from ornithine and its subsequent oxidative cyclization to the slagenin core. 相似文献
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We have designed, grown and fabricated InAs/InP quantum dot (QD) waveguides as the gain materials of mode-locked lasers (MLLs). Passive InAs/InP QD MLLs based on single-section Fabry-Perot (F-P) cavities with repetition rates from 10 GHz to 100 GHz have been demonstrated in the C- and L-band. Femtosecond (fs) pulses with pulse duration of 295 fs have been achieved. The average output power is up to 50 mW at the room temperature of 18 °C. By using the external fiber mixed cavities fs pulse train with a repetition rate of 437 GHz has been generated. We have also discussed the working principles of the developed QD MLLs. 相似文献
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Boehly TR Goncharov VN Seka W Barrios MA Celliers PM Hicks DG Collins GW Hu SX Marozas JA Meyerhofer DD 《Physical review letters》2011,106(19):195005
The fuel entropy and required drive energy for an inertial confinement fusion implosion are set by a sequence of shocks that must be precisely timed to achieve ignition. This Letter reports measurements of multiple spherical shock waves in liquid deuterium that facilitate timing inertial confinement fusion shocks to the required precision. These experiments produced the highest shock velocity observed in liquid deuterium (U(s) = 135 km/s at ~2500 GPa) and also the first observation of convergence effects on the shock velocity. Simulations model the shock-timing results well when a nonlocal transport model is used in the coronal plasma. 相似文献
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Cover Picture: From the Lindlar Catalyst to Supported Ligand‐Modified Palladium Nanoparticles: Selectivity Patterns and Accessibility Constraints in the Continuous‐Flow Three‐Phase Hydrogenation of Acetylenic Compounds (Chem. Eur. J. 20/2014) 下载免费PDF全文
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M. Suárez Barrios M. A. Vicente-Rodríguez J. M. Martín Pozas 《Journal of inclusion phenomena and macrocyclic chemistry》1996,24(3):263-272
The retention of nicotine by a high surface area saponite has been studied using two methods: (1) in repose at room temperature, and (2) heating at 70 °C under reflux. Different contact times were considered for each method. The intercalation compounds obtained were studied by chemical analysis, X-ray diffraction, infrared spectroscopy and thermal analysis. Nicotine is retained both in the interlayer region and at the edge of clay particles. The amount of nicotine retained in the interlayer region has been calculated from thermal analysis and CHN measurements. 相似文献
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