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21.
H. v. Brandis F. E. Wagner J. A. Sawicki K. Marcinkowska J. H. Rolston 《Hyperfine Interactions》1990,57(1-4):2127-2131
The state of iridium on Pt?Ir catalysts prepared by impregnation of amorphous silica with H2IrCl6 and H2PtCl6 was studied by193Ir Mössbauer spectroscopy after different steps of preparation. The Ir is adsorbed in its trivalent state, presumably as [IrCl6]3?. Calcination in air at 450°C converts this to IrO2. The metallic clusters formed by subsequent reduction in H2 at 200°C show a strong tendency towards segregation of Ir and Pt and re-oxidize partially when exposed to air at ambient temperature. In both respects the behaviour is similar to that of samples prepared by co-exchange from [Ir(NH3)5Cl]Cl2 and Pt(NH3)4Cl2. H2O. 相似文献
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S. Patzer N.L. Arthur P. Potzinger H.Gg. Wagner 《Journal of photochemistry and photobiology. A, Chemistry》1997,110(3):2543-227
The photolysis of Me6Si2 at 206 nm results in two main decomposition processes: simple Si---Si bond breaking with a quantum yield of Φ = 0.21 ± 0.03, and Me3SiH elimination with the concomitant formation of Me2SiCH2 with Φ = 0.18 ± 0.01. There is also a minor decomposition channel with a very small quantum yield, Φ = (5.6 ± 0.2) × 10−3, which results in the formation of Me4Si and Me2Si. The main fate of the excited Me6Si2 molecule produced during photolysis is stabilization by collisional deactivation. The end products observed indicate that the reaction pathways followed by the main intermediates, Me3Si and Me2SiCH2, are the same as those found in the photolysis of Me4Si (Ahmed et al., J. Photochem. Photobiol. A: Chem. 86 (1995) 33). 相似文献
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A. Mandelis W. Lo R. E. Wagner 《Applied Physics A: Materials Science & Processing》1987,43(2):123-130
The electrical and dielectric properties of mercuric iodide were studied at room temperature under various intensities and colours of light in the frequency range 1 Hz–10 kHz. In the high-frequency region (>40 Hz), the real part of the dielectric constant () is almost constant with frequency (f), colour and intensity of light. At lower frequencies, varies nearly as 1/f and monotonically increases with intensity (I) of the yellow (or green) light, whereas it is almost constant with red light intensity. This behaviour is discussed in the view of the different polarization contributions. The imaginary part of the dielectric constant () was found to vary as 1/f over the frequency range studied. This behaviour was observed whether the crystal was in dark or illuminated implying that the roomtemperature ac dark- or photo-conductivity () is independent of frequency. The observed variation of with intensity of yellow (or green) light was found to follow anI
1/2 dependence and a weaker dependence for the red light. the red light. The conductivity behaviour is discussed in the view of the current theories. 相似文献
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Wagner F Gruber O Lackner K Murmann HD Speth E Becker G Bosch HS Brocken H Cattanei G Dorst D Eberhagen A Elsner A Erckmann V Fussmann G Gehre O Gernhardt J Gierke Gv Glock E Grieger G Grigull P Haas G Hacker H Hartfuss HJ Jäckel H Jaenicke R Janeschitz G Junker J Karger F Kasparek W Keilhacker M Kick M Klüber O Kornherr M Kroiss H Kuehner M Lenoci M Lisitano G Maassberg M Mahn C Marlier S Mayer HM McCormick K Meisel D Mertens V Müller ER Müller Müller G Niedermeyer H Ohlendorf W 《Physical review letters》1986,56(20):2187-2190
30.
Substituierte 2-(Thiazol-4-yl)-phenole als Liganden und potentielle Extraktionsmittel für Kupfer(II)
Substituted 2-(Thiazol-4-yl)-phenols as Ligands and Potential Extractants for Copper (II) Substituted 2-(thiazol-4-yl)-phenols are obtained by the HANTZSCH synthesis. Their solubility in toluene is higher than in n-octane depending on the position, the chain length, and the polarity of the substituents. From alcoholic solutions complexes of the type CuL2n are precipitated. According to the substituents their structure is distorted octahedral (CuL22, CuL23) or distorted tetrahedral (CuL28, CuL29). The new complexes are nearly insoluble in toluene and aliphatic hydrocarbons, but CuL28 and CuL29 are soluble in chloroform. Therefore copper(II) may be extracted by HL8 and HL9 using chloroform as a diluent. 相似文献