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81.
A reductive transmetalation of the pi-allylpalladium(II) complexes, generated in situ from a catalytic amount of a palladium(0) complex and a variety of allylic substrates, with indium(I) salts proceeded smoothly in various solvents, providing a new route for allylindium(III) reagents. 相似文献
82.
1.5-mum emissions from Nd:YAG, Nd:YVO(4), and LiNdP(4) O>(12) microchip lasers pumped by laser diodes have been observed. These coherent emissions are attributed to the effect of high-energy modified lattice vibration owing to the existence of Nd ions as well as to stimulated intracavity Raman scattering enhanced by the microchip configuration. A four-wave mixing process involving two lasing fields and a Stokes field was identified as the generator of new adjacent 1.5-mu;m emission. 相似文献
83.
By using the historical data from the Japanese banks’ database at “The Bankers Library” of Japanese Banker Association, we analyze the historical network of banks from 1868 to 2006. Firstly, we define a bank every year by a particle and draw a space-time evolution process of merger, division, establishment, and failure by a tree diagram structure. We found that the distribution of the tree basin size of real data and simulation result are mostly fitting well. Secondly, we analyze the raw data of financial statements of banks collected by the National Diet library. We confirm that the distributions of the amount of deposits have fat-tail every year, however, small deviations are observed relating to governmental policy. 相似文献
84.
A.K.M. Akther Hossain K. Khirul Kabir T. Kawai 《Journal of Physics and Chemistry of Solids》2007,68(10):1933-1939
Structural, AC and DC magnetic properties of polycrystalline Zn1−xCoxFe2O4 (x=0.2, 0.4) samples sintered at various temperatures (1100-1300 °C), and various dwell times (0.2-15 h) have been investigated thoroughly. The bulk density of the Zn0.60Co0.40Fe2O4 samples increases as the sintering temperature (Ts) increases from 1100 to 1250 °C, and above 1250 °C the bulk density decreases slightly. The Zn0.80Co0.20Fe2O4 samples show similar behavior of changes to that of Zn0.60Co0.40Fe2O4 samples except that the bulk density is found to be highest at 1200 °C. The DC magnetization as a function of temperature curves show that the Zn0.60Co0.40Fe2O4 sample is ferrimagnetic at room temperature while the Zn0.80Co0.20Fe2O4 sample is paramagnetic at room temperature. The Tc of Zn0.80Co0.20Fe2O4 sample is found to be 170 K from DC magnetization measurement. Separate measurement (AC magnetization), initial permeability as a function of temperature shows that the Tc of the Zn0.60Co0.40Fe2O4 sample is 353 K. Slight variation of Tc is observed depending on sintering condition. The initial permeability for the Zn0.60Co0.40Fe2O4 composition sintered at 1250 °C is found to be maximum. 相似文献
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