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101.
Isao Saito Shigeru Muramatsu Hiroshi Sugiyama Akihiro Yamamoto Teruo Matsuura 《Tetrahedron letters》1985,26(48):5891-5894
Photochemical hydrogen-deuterium exchange reaction of biologically important indoles is reported. The regioselectivity of the photodeuteration was found to be controlled by the ammonium group of the side chain. 相似文献
102.
Jun-ichi Watanabe Tomoyuki Sekine Kunimitsu Uchinokura Etsuyuki Matsuura 《Solid State Communications》1984,51(5):289-291
An increase in Raman intensity of surface phonon polaritons has been observed in free-standing thin slabs (thickness ~ 7 μm) of single- crystal ZnTe with rough surfaces by a conventional Raman-scattering technique at room temperature. The samples with various root-mean- square roughness heights have been prepared by making use of final polishing powders with different mean-grit sizes, and the surface roughness has been confirmed by measuring the intensities of the diffuse scattering of the laser light. The increase of the Raman intensity is proportional to the mean-square height of the surface roughness, and the shift of the dispersion relation is also proportional to it. The frequency shift is explained by a perturbation theory of the surface-roughness-induced scattering. 相似文献
103.
3-Chloro-2,5-dimethylpyrazine 1-oxide underwent cross-coupling with dialkylzinc reagents forming 3-alkyl-2,5-dimethylpyrazine 1-oxides. The reaction was realized by catalytic 1,3-bis(diphenylphosphino)-propane nickel(II) chloride and the optimum results were examined. 相似文献
104.
Among amorphous Fe2RE (RE=Er, Ce, Gd, La, Pr, Sm, Dy, Ho) alloys, Fe2Ce exhibits a tendency toward short range order, while the other Fe2RE compounds show clustering. However, we have almost no information about environments around Fe atoms. Using Mössbauer spectroscopy we have determined the quadrupole splitting distributionsP(QS) of two representative amorphous Fe2RE (RE=Ce, Er) alloys, leading to local environments of Fe atoms. The analysis of the mixed magnetic dipole and quadrupole interactions in Fe2Er shows two kinds of electrical field gradients (EFT) with the positive and negative signs in the sample, indicating a random packing of Fe atoms. Furthermore, the analyzed quadrupole splitting distributionP(QS) of Fe2Er also supports random packing in this amorphous alloy. On the other hand, the amorphous Fe2Ce alloy shows two kinds of distributions of quadrupole splitting; the major component indicating random packing and the minor component Ce-rich Ce-Fe clusters. 相似文献
105.
106.
107.
Yoshihiko Ito Hiroshi Imai Takaharu Matsuura Takeo Saegusa 《Tetrahedron letters》1984,25(29):3091-3094
This paper describes the finding that BF3 etherate effectuates the conjugate additions of copper(I) aldimines, generated in situ from lithium aldimines and Cu(I) halide, to α,β-unsaturated carbonyl compounds to produce 4-(N-alkylimino)-ketones, which give on acid hydrolysis 1,4-diketone derivatives. 相似文献
108.
Tomoyuki Sekine Kunimitsu Uchinokura Mitsuru Izumi Etsuyuki Matsuura 《Solid State Communications》1984,52(4):379-383
The phase transition of the linear chain compound (NbSe4)3I was studied by Raman scattering. At 78 K three new peaks were observed at 73 cm?1, 205 cm?1 and 261 cm?1. The totally symmetric Raman peak at 73 cm?1 shows anomalous temperature dependence. The frequency decreases with increasing temperature, and at high temperatures an anticrossing occurs with another peak observed at about 58 cm?1. The Raman intensity decreases and the linewidth broadens remarkably as the temperature increases. These properties allow us to assign this peak to a soft phonon. This fact indicates clearly the existence of a structural phase transition of a displacive type below room temperature. 相似文献
109.
The efficiency of oxygen transfer from the transannular ozonide 1 to several organic substrates was investigated. The efficiency was estimated to be as high as 90% in the case of Ph3P as the substrate. 相似文献
110.
Stability for self-trapping of a Wannier exciton in the polarization field of optical phonons is studied by means of variational calculations based on the adiabatic approximation. The phase diagram of free and self-trapped states is presented for 1s, 2s and 2p excitons. It is shown that optical phonons can be responsible for self-trapping of 2s (2p) exciton as a trigger of self-trapping. 相似文献