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91.
92.
Satoru Nakashima Yuichi Masuda Izumi Motoyama Hirotoshi Sano 《Hyperfine Interactions》1988,40(1-4):319-322
It was found that the packing of cations and anions influences the electronic structures of mixed-valence binuclear ferrocene derivatives. Temperature-dependence of the mixed-valence state of 11, 1111-diisobutylbiferrocenium triiodide was observed in a crystalline state, whereas only a trapped-valence state was found in a dispersed state. The packing effect was also observed for a series of 11, 1111-dialkyl- and 11, 1111-bis(methylbenzyl)biferrocenium triiodides by means of ESR spectroscopy. 相似文献
93.
Fatigue of the luminescence in amorphous SiH alloys has been investigated as a function of dangling bond density and of hydrogen content at 2 K. Optically detected magnetic resonance measurements have also been carried out to elucidate the origin of the fatigue effect for those samples. 相似文献
94.
95.
The molecular motions in the three phases of 1,1′,2,2′-tetrachloroferrocene below m.p. were studied by using57Fe-Mossbauer and1H FT-NMR spectroscopy. In the plastic phase at the low temperature, a rotational mode around the pseudo C5 molecular axis was found to be activated with activation energy of 15 kJ/mol and in the higher temperature phase the rotational
mode of the pseudo C5 axis itself was found to be activated with activation energy of 23 kJ/mol in addition to the rotational mode around the pseudo
C5 axis. On the57Fe-Mossbauer spectra, a steep decrease of the areal intensity was observed above the first transition temperature. The areal
intensity in the lower plastic phase was estimated to be less than a few percent relative to that at 298 K. The results were
discussed in terms of different possibilities for the movement of the molecules. 相似文献
96.
97.
Radiative and nonradiative recombination processes have been investigated by measurements of optically detected magnetic resonance at 2 K in hydrogenated anorphous silicon. Relevant processes are discussed on the basis of the experimental results. 相似文献
98.
99.
Numerous peptide aptamers that recognize inorganic materials have been isolated using in vitro peptide evolution systems. However, it remains unknown how peptides interact with inorganic materials or how specific those interactions are. We, therefore, assessed the target specificities of the peptide aptamer TBP-1 (RKLPDAPGMHTW) by monitoring its ability to bind 10 different metals. We found that phages displaying TBP-1 bound to Ti, Si, and Ag surfaces but not to Au, Cr, Pt, Sn, Zn, Cu, or Fe. As previously seen with Ti, binding to Si and Ag was diminished by R1A, P4A, or D5A mutation, suggesting that the same molecular mechanism underlies TBP-1 binding to all three materials. We also observed that a synthetic TBP-1 peptide mediated mineralization of both silica and Ag. It, thus, appears that although the overall chemical characteristics of Ti, Si, and Ag surfaces are dissimilar, they share a common subnanometric structure that is recognized by TBP-1. 相似文献
100.
Novel chiral phosphonoacetates bearing a stereogenic phosphorus atom were successfully synthesized by enzyme-catalyzed kinetic resolution of racemic phosphonoacetates. 相似文献