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Application of the sum peak method to indium solutions in hydrochloric acid has been studied. A calibration line to determine a PAC parameter \(\overline {G_{22} } \) has been adopted using two samples with known values of \(\overline {G_{22} } \) . The results show feasibility of the method because of its simplicity and of smaller amounts of radioactivity required in the measurement compared to the ordinary PAC method. 相似文献
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A nitro group in nitroolefins is displaced by hydrogen giving the corresponding olefins in good yields by the reaction of nitroolefins with sodium sulfide in the presence of benzenethiol. It proceeds rapidly at room temperature. 相似文献
116.
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
117.
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
118.
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
119.
Koichiro Fukuda Akira Moriyama Tomoyuki Iwata 《Journal of solid state chemistry》2005,178(6):2144-2151
The crystal structure of BaZr(PO4)2 at 298 K was determined from conventional X-ray powder diffraction data using direct methods, and it was further refined by the Rietveld method. The structure was monoclinic (space group C2/m, Z=2) with , , , β=93.086(1)° and . Final reliability indices were Rwp=8.21%, Rp=5.64% and RB=2.92%. The atom arrangement is similar to that of yavapaiite (KFe(SO4)2), however, these crystal structures differ distinctly in the coordination numbers of barium and potassium atoms; the former is tenfold coordinated, whereas the latter is sixfold coordinated. The powder specimens were also examined by high-temperature XRD and DTA to reveal the occurrence of a phase transition from monoclinic to orthorhombic at 732 K during heating. Upon cooling the reverse transition occurred at 710 K. The monoclinic crystal expanded almost one-dimensionally along [503] during the heating process. The orthorhombic phase also showed a tendency to expand one-dimensionally along the c-axis above 732 K. 相似文献
120.
Masaki Kita Tomoyuki Koyama Hiroshi Matsumoto Daisuke Uemura 《Tetrahedron letters》2005,46(49):8583-8585
The muricid gastropods genus Drupella are known to be voracious coral predator. Outbreaks of them have accelerated significant destruction on coral reefs, but its precise mechanism is poorly understood. Here, we describe the identification of montiporic acids C (1) and A (2) isolated from sea water extracts of the coral Montipora sp., which showed potent feeding-attractant activity toward D. cornus. 相似文献