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61.
JPC – Journal of Planar Chromatography – Modern TLC - 相似文献
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V. Turchanikov A. Nazarov V. Lysenko V. Ostahov O. Winkler B. Spangenberg H. Kurz 《Microelectronics Reliability》2007,47(4-5):626
This paper focuses on the detailed study of the unipolar recharging phenomenon of the nanocluster NVM cells based upon the electron emission from the nanodots and their subsequent neutralization. It is shown that electron emission from nanodots is a very fast and effective process with a time constant <5 ms, but the subsequent neutralization of the positive accumulated charge is strongly dependent on the excess of Si atoms stored in the nanodots. 相似文献
65.
Taketoshi Matsumoto Patricia Nickut Kazuya Watanabe Tatsuya Tsukuda Katharina Al-Shamery 《Surface science》2007,601(22):5226-5231
Reduction of oxidized gold nanoclusters by exposures to foreign gases and irradiation of UV photons has been investigated using X-ray photoelectron spectroscopy. Gold nanoclusters with narrow size distributions protected by alkanethiolate ligands were deposited on a TiO2(1 1 0) surface with dip coating. Oxygen plasma etching was used for removal of alkanethiolate ligands and oxidization of gold clusters. The oxidized gold clusters were exposed to CO, C2H2, C2H4, H2, and hydrogen atoms. Although, C2H4 and H2 did not show any indications of reduction of oxidized gold clusters, CO, C2H2, and hydrogen atoms reduced the oxides on gold cluster surfaces. Among them, hydrogen atoms were most effective for reduction. Irradiation of UV photons around 400 nm could also reduce the oxidized gold clusters. The photochemical reduction mechanism was proposed as follows. The photo-reduction was initiated by electronic excitation of gold clusters and oxygen atoms activated reacted with carbon atoms at the surfaces of gold clusters. Carbon species were likely absorbed in gold clusters or remained at the boundaries between gold clusters when gold clusters agglomerated during oxygen plasma exposures. As the photochemical reduction progressed, carbon atoms segregated to the surfaces of gold clusters. 相似文献
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Katharina M. Fromm Helmut Goesmann 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):1179-1180
We have been able, via a new synthetic route, to obtain a complete crystal structure of the title compound, tetraaquabarium hydroxide iodide, [Ba(OH)I(H2O)4], for which the heavy atoms only were characterized by Kellersohn, Beckenkamp & Lutz [Z. Naturforsch. TeilB (1991), 46 , 1279–1286]. In the present results, the H‐atom positions could be located using X‐ray data collection at low temperature. A three‐dimensional network is built up via hydrogen bonds. It was also observed that the title compound undergoes hydrolysis and might therefore be regarded as an intermediate in the formation of sol–gels, starting from BaI2 and leading to [Ba(OH)2(H2O)x]. 相似文献
69.
A. Faber A. Lemke B. Spangenberg M. Bolte 《Acta Crystallographica. Section C, Structural Chemistry》1999,55(11):IUC9900156-IUC9900156
70.
Karl Hensen Ralf Mayr‐Stein Bjrn Spangenberg Michael Bolte 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):610-613
The reaction products of an addition reaction of five different silicon tetrahalides with the aromatic nitrogen base 4‐methylpyridine are presented. The following five structures are isomorphous: (I) tetrachlorobis(4‐methylpyridine)silicon, C12H14Cl4N2Si, (II) bromotrichlorobis(4‐methylpyridine)silicon, C12H14BrCl3N2Si, (III) dibromodichlorobis(4‐methylpyridine)silicon, C12H14Br2Cl2N2Si, (IV) tribromochlorobis(4‐methylpyridine)silicon, C12H14Br3ClN2Si, and (V) tetrabromobis(4‐methylpyridine)silicon, C12H14Br4N2Si. The molecules of (I) and (V), with D2h symmetry, have crystallographic C2h symmetry, while the molecules of (II), (III) and (IV) have a lower molecular symmetry, but as a result of the disorder of the halogen ligands, they appear to be of the same crystallographic symmetry. The environment around the Si atom can be described as a slightly distorted octahedron with the methylpyridine ligands occupying axial positions and the four halogen ligands in the equatorial plane. In spite of the different substitution pattern of the silicon centre, there are only insignificant differences between these five structures. 相似文献