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901.
Yoshihiro Saito Masahiko Chikuma Akimasa Iwado Yutaka Saito 《Fresenius' Journal of Analytical Chemistry》1994,348(11):776-777
Thiosalicylic acid selenotrisulfide(SeT) was prepared by the reaction of thiosalicylic acid and selenious acid in methanol. The precipitated SeT was partially purified by an extensive washing with methanol and pure SeT was isolated by preparative high-performance liquid chromatography (HPLC) using a reverse phase column. The HPLC method was useful both in the analysis and the isolation of SeT. 相似文献
902.
We have generated thep-cyanobenzyl radical in supersonic free expansion, and measured the vibrationally and rotationally resolved laser induced fluorescence (LIF) excitation spectra and the LIF dispersed spectra from the single vibronic levels (SVL) in the green-blue region. The lowest energy band at 20 738 cm−1with the strongest intensity in the excitation spectrum has been assigned to the 000band of the visible spectrum, on the basis of the vibronic structures in the SVL dispersed spectra. Based on the band type of the 000band,a-type, determined from the rotationally resolved LIF excitation spectrum, we have definitely assigned the visible band to theD122B1–D012B1electronic transition. We have found, on the grounds of the vibrational analysis of the dispersed spectra, that the vibronic structure of the 22B1–12B1electronic transition of the benzyl type is characterized by totally symmetric fundamental modes, 1, 8a, and 9a. 相似文献
903.
904.
905.
Bis-aluminated trifluoromethanesulfonamide generated in situ by mixing TfNH2 (1 mol) and methylaluminum reagent (2 mol) is an effective catalyst for the IMDA reaction of ester-tethered 1,7,9-decatrienoates. 相似文献
906.
907.
908.
The temperature-dependent site selectivities of Cs and Rb ions in CsRb2C60 and Cs2RbC60 superconductors are computed using the free energy obtained from the configuration entropy and the total energy calculated using the ab initio pseudopotential density-functional theory. It is found that in CsRb2C60 the smaller Rb ions can occupy a considerable number of large octahedral interstitial sites at high temperatures, however, the transition to random occupation never takes place. For Cs2RbC60 the Cs occupancy of the large octahedral interstitial sites is almost always 100%, and, interestingly, the two tetrahedral interstitial sites are randomly occupied by Cs and Rb ions even at very low temperatures. 相似文献
909.
910.
We discuss the Noether-Lefschetz locus for Beilinson's Hodge cycles. Here ``Beilinson's Hodge cycles' mean the cohomology
class of Bloch's higher Chow cycles on smooth varieties. The main result is to give an estimate of the dimension of the maximal
component of the Noether-Lefschetz locus for the universal family of open complete intersections. 相似文献