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171.
Takashi Kamimura Masaki Sato Takao Iwata 《Journal of magnetism and magnetic materials》1987,70(1-3):209-210
Transitions related to the spin-glass phase in Mn1−xTixSb
are revisited from the nonlinear ac susceptibility. Near the tricritical point (x≈0.8), the transition between ferromagnetic and reentrant spin-glass states is sharp. At x0.8, an anomally is found slightly above the temperature of usual spin-glass freezing. 相似文献
172.
173.
Fumio Kawamura Masaki TanpoNaoya Miyoshi Mamoru ImadeMasashi Yoshimura Yusuke MoriYasuo Kitaoka Takatomo Sasaki 《Journal of Crystal Growth》2009,311(10):3019-3024
We have discovered a mechanism which can significantly reduce the dislocation density during the growth of GaN single crystals in the Na flux method. The significant reduction of the dislocation density occurs in the later stage of LPE growth, rather than solely at the seed-LPE interface for which we have already reported evidence indicating the presence of bundling dislocations. The two-step dislocation reduction is the key in achieving extremely low dislocation density using this method. 相似文献
174.
175.
Tatsuya Suzuki Yasuhiko Fujii Wu Yan Hitoshi Mimura Shin-ichi Koyama Masaki Ozawa 《Journal of Radioanalytical and Nuclear Chemistry》2009,282(2):641-644
We investigated the adsorption behaviors of technetium and rhenium on tertiary pyridine resin in hydrochloric acid solution.
Technetium has a little larger distribution coefficient in higher concentration of hydrochloric acid region than rhenium.
However, the tendency of adsorption behavior of technetium and rhenium is similar. We concluded that the rhenium can be used
as the substitute for technetium. Adsorption behaviors of platinum group elements were also investigated. The separation of
technetium from platinum group elements is discussed. 相似文献
176.
177.
Yoshinari Awaji Hideaki Furukawa Naoya Wada Eddie Kong Peter Chan Ray Man 《Optical and Quantum Electronics》2008,40(5-6):461-466
The WDM flatness easily collapses due to substantial changes in input power, an inherent problem in optical packet communication because of dynamic changes in traffic density. We propose a burst-mode EDFA with a novel configuration based on the concept of a mid-position gain flattening filter (GFF) with overpumping. This configuration can effectively suppress gain transience while maintaining WDM flatness. 相似文献
178.
179.
Atsuya Muranaka Masaki Yokoyama Yotaro Matsumoto Masanobu Uchiyama Akihiko Tsuda Atsuhiro Osuka Nagao Kobayashi 《Chemphyschem》2005,6(1):171-179
The magnetic circular dichroism (MCD) spectra of doubly and triply linked fused bisporphyrins (2MD and 2MT, M = Ni, Zn, Cu, Pd, and H2) and triply linked higher oligomers (3ZnT and 4ZnT) have been measured, and their Q-bands assigned based on the results of INDO/s calculations. In contrast to the Faraday A term observed for the Q(0,0) band of Ni(II) tetraphenylporphyrin, a single positive Faraday B term was observed for the lowest energy transition of the fused systems. The calculations indicated that the molecular orbitals (MOs) of the directly fused porphyrins consist of linear combinations of the constituent monomeric MOs, and that the effect of lowering the symmetry is always larger on the lowest unoccupied molecular orbital (LUMO) than on the highest occupied molecular orbital (HOMO). On the basis of Michl's perimeter model, these features can be correlated with the observed positive MCD signs in the near infrared region. A weak absorption band at 600-700 nm for the fused dimers can be assigned to a short-axis polarized Q transition. 相似文献
180.