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921.
922.
A short, efficient synthesis of 22-hydroxyacuminatine, starting from a readily accessible hydroxy pyridone, is presented; key steps include a Heck coupling with methyl pentadienoate, a flash vacuum pyrolytic cyclization, and a Friedl?nder condensation. 相似文献
923.
Guo J Stockwell D Ai X She C Anderson NA Lian T 《The journal of physical chemistry. B》2006,110(11):5238-5244
Photoinduced electron injection dynamics from Ru(dcbpy)(2)(X)(2) (dcbpy = 4,4'-dicarboxy-2,2'-bipyridine; X(2) = 2SCN(-), 2CN(-), and dcbpy; referenced as RuN3, Ru505, and Ru470) to In(2)O(3) nanocrystalline thin films were studied using ultrafast transient IR absorption spectroscopy. After 532 nm excitation of the adsorbates, the dynamics of electron injection from their excited states to In(2)O(3) were studied by monitoring the IR absorption of the injected electrons in the semiconductor. The injection kinetics were non-single-exponential. For samples exposed to air, the half rise times, defined as the time of 50% injection yield, were 5 +/- 0.8, 85 +/- 20, and >200 ps for RuN3, Ru505, and Ru470, respectively. For samples in pH 2 buffer, the corresponding half time for injection from these complexes became 6 +/- 1, 105 +/- 20, and 18 +/- 5 ps. The injection kinetics from RuN3 to In(2)O(3) was found to be similar to that to SnO(2). These kinetics traces showed a negligible <100 fs injection component and were very different from those to TiO(2). The dependences of the injection kinetics on adsorbate energetics and the nature of the semiconductors are discussed. 相似文献
924.
Petravic M Deenapanray PN Fraser MD Soldatov AV Yang YW Anderson PA Durbin SM 《The journal of physical chemistry. B》2006,110(7):2984-2987
We have used synchrotron-based near-edge X-ray absorption fine structure (NEXAFS) spectroscopy to study the electronic structure of nitrogen-related defects in InN(0001). Several defect levels within the band gap or the conduction band of InN were clearly resolved in NEXAFS spectra around the nitrogen K-edge. We attribute the level observed at 0.3 eV below the conduction band minimum (CBM) to interstitial nitrogen, the level at 1.7 eV above the CBM to antisite nitrogen, and a sharp resonance at 3.2 eV above the CBM to molecular nitrogen, in full agreement with theoretical simulations. 相似文献
925.
926.
J. Houben Julius Meyer F. P. Treadwell F. Heeren H. G. Martin Cl. E. Williams Arvid E. Anderson C. E. Sims B. M. Larsen E. Terres A. Pongracz H. C. M. Ingeberg F. Foerster V. Herold E. S. Peck G. Frerichs V. Coblentz O. B. May Edgar Thompson Steel Works A. D. Horlück A. Eberhard E. Schmidt Fr. Wüst N. Kirpach L. Schneider J. Parry J. J. Morgan und E. Diepschlag 《Fresenius' Journal of Analytical Chemistry》1927,71(8):297-311
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927.
The angular distribution of photoelectrons ejected from benzene using 21.22 eV radiation has been measured and the results applied to the analysis of the ionization bands. 相似文献
928.
929.
Identification of microorganisms in biofluids of individuals with periodontitis and chronic kidney disease using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry 下载免费PDF全文
930.
N. H. Furman E. B. Wilson W. G. Leeman B. Park E. J. Lewis C. W. Anderson und Le Roy W. Mc Cay 《Fresenius' Journal of Analytical Chemistry》1936,104(5-6):211-213
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