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751.
K.B. Garg Hisashi Hayashi A. Sato T. Azumi Y. Udagawa Kenji Ishii Toshiya Inami T. Chatterji 《Journal of magnetism and magnetic materials》2008
Spin-selected polarized X-ray absorption near-edge structures (SSXANES) at the Mn K-edge from a bilayer La1.2Sr1.65Ca0.15Mn2O7 single crystal have been studied with high resolution, both in the ferromagnetic (15 K) as well as paramagnetic phase (300 K). The orientation-dependent SSXANES spectra show unmistakable temperature dependence as the system makes the ferromagnetic to paramagnetic phase transition. The pre-edge structures are too intense to be ascribed to weak quadrupole transitions and are interpreted in terms of hybridization of Mn 3d orbitals with O2p and Mn 4p orbitals over and above similar onsite hybridization. The results also indicate possible existence of a small local (time-frozen) ferromagnetic ordering in the macroscopically disordered state. Need for further experimental and theoretical work on the SSXANES spectra from the bilayer system is emphasized. 相似文献
752.
We discuss cluster phenomena in light nuclei. As examples of typical cluster structures, we first review cluster structures of 12C, 16O, and 20Ne, and then introduce some topics of cluster phenomena in light neutron-rich nuclei such as Be and C isotopes. A particular attention is paid on coexistence of cluster and shell-model aspects. 相似文献
753.
Masayoshi Tonouchi Akihiko Itoh Takashi Yasuda Hisashi Shimakage Zhen Wang Shuzo Takano 《Czechoslovak Journal of Physics》1996,46(Z3):1275-1276
We fabricatedc-axis oriented meas on YBa2Cu3O7−δ thin films. Columnar structures with an area of 20×20 μm2 and a depth of 0.1 μm were formed on oxygen deficient films with a critical temperature (T
c
) of 64 K or less. The devices showed hysteretic I–V curves without any branches. The dependence of the critical current density
on the temperature nearT
c
is explained by the Ambegaokar-Baratoff relation. 相似文献
754.
When the electron-electron interaction is explicitly considered in many-electron atoms, the average electron radius (r) splits into the inner (r<) and outer (r>) radii. It is shown that the sum and difference of these radii constitute upper and lower bounds, respectively, to the electron-pair relative distance r(12)=(/r1-r2/). An analogous result is also derived for the electron-pair center-of-mass radius (R)=(/r1+r2//2). For the 102 atoms He through Lr in their ground states, the tightness of these bounds is numerically examined at the Hartree-Fock limit level. Good linear correlations are observed between (r12) and (r>), and between (R) and (r>)/2. 相似文献
755.
756.
Xie H Wang T Matsuda H Morikawa T Yoshikawa M Tani T 《Chemical & pharmaceutical bulletin》2005,53(11):1416-1422
The 80% aqueous acetone extract from the whole plant of Saussurea medusa MAXIM. was found to inhibit rat lens aldose reductase (IC50=1.4 microg/ml). From this extract, flavonoids, lignans, and quinic acid derivatives were isolated together with two new ionone glycosides, saussureosides A and B. Their absolute stereostructures were elucidated on the basis of chemical and physicochemical evidence including the application of modified Mosher's method. In addition, some isolates were found to show an inhibitory effect on aldose reductase. 相似文献
757.
Takahisa Anada Masako Ogawa Hisashi Yokomizo Yoshihisa Ozaki Tohru Takarada Yoshiki Katayama Mizuo Maeda 《Analytical sciences》2003,19(1):73-77
We describe here a method of affinity capillary electrophoresis in which oligodeoxynucleotide (ODN) was immobilized onto the inner surface of the capillary. The immobilized ODN functioned successfully as an affinity ligand for sequence-based DNA separation. Six- or 12-mer ODN with a sequence complementary to one of the c-K-ras gene was used as an immobilized ligand. When the 12-mer ODN was used, the detection peak for the complementary ODN disappeared selectively, while the single-base mutant was detected as usual. In contrast, when the 6-mer ODN was used as the affinity ligand with a mixture of the complementary ODN and its single-base mutant, it was possible to detect both as completely separate peaks. That is, the separation mode was dependent on the base number of the immobilized ODN used as an affinity ligand. 相似文献
758.
759.
Y Ohishi T Mukai M Nagahara M Yajima N Kajikawa 《Chemical & pharmaceutical bulletin》1992,40(4):907-911
5-Alkyl-3-carboxymethylrhodanines (2) were prepared from 5-alkylmethylidene-3-carboxymethylrhodanines (1). The exo double bond of 1 was successfully reduced with NaBH4. The 1,4-addition reaction path was confirmed on the basis of proton nuclear magnetic resonance spectrum of the product (4b) obtained from the reduction of 3 using NaBD4. Optical resolution of the tert-butyl compound (2i) was achieved upon epimerization-crystallization method using L-3-amino-epsilon-caprolactam. The alkyl compounds (2) and the optical active compounds ((+)-2i, (-)-2i) were evaluated for aldose reductase inhibitory potency. 相似文献
760.