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71.
72.
Isao Watanabe Kusuo Nishiyama Kanetada Nagamine Kenji Kawano Ken-ichi Kumagai 《Hyperfine Interactions》1994,86(1):603-608
Zero field positive muon spin rotation method (
+SR) is applied on La2–x
Sr
x
CuO4 around forx=0.12 at which the high-T
c
superconductivity (SC) is suppressed. The magnetically ordered state of Cu-moments, which is not a spin glass state but an antiferromagnetic like state, appears below 15 K for 0.105x0.120. The magnetic phase boundary is very similar to the one of the La2–x
Ba
x
CuO4 in which the structural transition from the low temperature orthorhombic (LTO) phase to the low temperature tetragonal (LTT) phase is observed aroundx=0.12. The present study suggests that there is no big difference of the electronic state of the CuO2 plane between the La-Ba system and the La-Sr system and that the magnetic ordering of Cu-moments plays an important role for the suppression of the high-T
c
SC aroundx=0.12 in both of the systems, although the LTO-LTT structural transition has not been observed yet in the La-Sr system. 相似文献
73.
74.
75.
Kenji Kojima Kusuo Nishiyama Kanetada Nagamine Hironobu Ikeda 《Hyperfine Interactions》1993,78(1-4):429-433
The site diluted finite spin cluster system Rb2CO
x
Mg1–x
F4 (x=0.15, 0.4, 0.5) has been investigated by the +SR technique. Muon spin relaxation was observed in these diluted magnetic systems in a weak longitudinal field of 100 G. By reducing temperature below 100 K, the experimental data show features of slowing down phenomena of the Co electron moments in the finite spin clusters. 相似文献
76.
4-Fluorinated UDP-MurNAc pentapeptide, 2, has been synthesized. In our previous study, UDP-MurNAc pentapeptide analogue 1 was found to be incorporated into the bacterial cell wall through biosynthesis. Compound 2 showed growth-inhibition activity against Gram-positive bacteria when it was added to growth media at 0.01 mg/mL. [structure--see text] 相似文献
77.
New low-molecular-weight gelators based on l-valine and l-isoleucine gelators, which have a positively charged terminal group, can gel not only pure water and aqueous solutions containing inorganic acids and salts but also some organic solvents and oils. 相似文献
78.
79.
N-Acyl-α-amino acids are synthesized by the amidocarbonylation of allylic alcohols catalyzed by homogeneous binary systems which consist of cobalt carbonyl and rhodium (or iron or palladium) complexes. 相似文献
80.
Takashi Hirota Kenji Sasaki Yohsuke Tashima Taiji Nakayama 《Journal of heterocyclic chemistry》1991,28(2):263-267
Syntheses of 2,3-dihydrobenzofuro[2,3-e]imidazo[1,2-c]pyrimidine and its 5-substituted derivatives, corresponding to B-nor-6-oxa-11,13,15-triazasteroids, are described. These products and their precursors were screened to evaluate the antidepressive activity. 相似文献