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21.
The photosensitized aquation of pentaammine(pyridine)ruthenium(II) by several dyes has been studied under conditions where only the sensitizers absorb light. The ratio of the quantum yields for ammine and pyridine substitution was the same as that for direct photoaquation. Sensitization was effective with singlet sensitizers Rhodamine-B (17 452 cm(-)(1)) and Safranine-T (17 690 cm(-)(1)), as well as the triplet sensitizer biacetyl (19 000 cm(-)(1)), but no reaction was observed with Neutral-Red (16 900 cm(-)(1)). The results indicate that the excited state precursor of the observed photosubstitution in the complex lies in the energy range between 17 000 and 17 700 cm(-)(1). 相似文献
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Klaus Rose Vlastimil MatĚjec Milos Hayer Marie PospiŠilovÁ 《Journal of Sol-Gel Science and Technology》1998,13(1-3):729-733
Various types of UV-curable organically modified siloxanes have been synthesized by the sol-gel method with the aim of fabricating chemically sensitive coatings for silica optical fibers. The refractive index of the coating material can be tailored in the range from 1.46 to 1.56 and sensitivity towards CO2 is achieved by incorporation of amino groups. The interaction of the cured layers with CO2 or with hydrocarbons has been studied in immersion experiments. Both the reaction of CO2 with incorporated amino groups and the penetration of hydrocarbons into the layer induce changes of the light absorption coefficient and the refractive index of the coating which are detected by measuring the output light intensity from the fiber. 相似文献
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Ash WW Band HR Blume HT Camporesi T Chadwick GB Coombes RW Delfino MC Fernandez E Ford WT Gettner MW Goderre GP Groom DE Heltsley BK Hurst RB Johnson JR Lau KH Lavine TL Leedy RE Lippi I Maruyama T Messner RL Moromisato JH Moss LJ Muller F Nelson HN Peruzzi I Piccolo M Prepost R Qi N Read AL Ritson DM Rosenberg LJ Shambroom WD Sleeman JC Smith JG Venuti JP von Goeler E Verdini P Wald HB Weinstein R Wiser DE Zdarko RW 《Physical review letters》1985,55(20):2118-2121
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Fernandez E Ford WT Qi N Read AL Smith JG Camporesi T De Sangro R Marini A Peruzzi I Piccolo M Ronga F Blume HT Hurst RB Venuti JP Wald HB Weinstein R Band HR Gettner MW Goderre GP Meyer OA Moromisato JH Shambroom WD Sleeman JC von Goeler E Ash WW Chadwick GB Clearwater SH Coombes RW Kaye HS Lau KH Leedy RE Lynch HL Messner RL Moss LJ Muller F Nelson HN Ritson DM Rosenberg LJ Wiser DE Zdarko RW Groom DE Lee H Delfino MC Heltsley BK Johnson JR Lavine TL Maruyama T Prepost R 《Physical review letters》1985,54(15):1620-1623
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E. -L. Lakomaa P. Manninen R. J. Rosenberg R. Zilliacus 《Journal of Radioanalytical and Nuclear Chemistry》1993,168(2):357-366
Two examples of the use of neutron activation analysis for the characterization of semiconductor materials are given. 23 elements were determined in ASTM silicon intercomparison samples. Most elements are below the detection limits, which vary between 0.009–300 ng/g. CdS/CdTe thin films have been characterized by determining the Cd, Te, Cl, I and In concentrations of dissolved films. Parallel determinations in different samples of films prepared under identical conditions agreed within 0–53% (average deviation 21%) for Cl, Cd, In and I in CdS and 1.6–22% (average 8.7%) for Cd and Te in CdS/CdTe, respectively. It was determined both by NAA and resonance ionization spectrometry (RIS). The order of magnitude of the results was 1 ng/g and they agree within the range 7–64% (average difference 25%). The analytical procedures are described and discussed. 相似文献