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91.
Mössbauer measurements on Fe0.068Ni0.932Cl2 were done at temperatures between 55K and 4.2K. We have found that below TN-50K an observed spectrum is composed of two kinds of spectra and that the composition ratio changes gradually with temperature. The average angle of Fe2+ spins, \(\overline {\theta _{Fe} } \) , with the c-axis is smaller than \(\overline {\theta _c } \) by ?15° at each temperature below TN, where \(\overline {\theta _c } \) is the average angle of total spins with the c-axis in this system obtained from the neutron scattering measurements. This is reasonably understood if we take into account that Fe2+ spins have the strong uniaxial anisotropy along the c-axis. We discuss the coexistence of the two kinds of spectra by considering the exchange energy of Fe2+ spins and the local magnetic anisotropy. 相似文献
92.
Y. Tamaki 《Journal of Radioanalytical and Nuclear Chemistry》1995,196(1):161-164
The VK X-rays induced by the electron capture decay of51Cr-labeled compounds and the fluorescent X-rays of the vanadium compounds have been measured with a Bragg spectrometer. The evident chemical shifts of the K1 and K2 lines were observed for the oxidation state both by electron capture and photoionization. The differences of the K peak energy (K1 and K2 peaks) with the modes of the excitation were also obtained. The K peaks of51Cr shift to lower energy by ca. 0.5 eV than those of vanadium at the same oxidation state. This is because the probability of the electron shake up (and shake off) during the electron capture decay is extremely small, as compared to photoionization. 相似文献
93.
Using a versatile synthesis with 13CH3PPh3I and CH(3)13CO2Et as 13C sources, the first examples of nine-membered chromophores which have been differentially labelled with 13C in their carbocyclic enediyne cores are described. 相似文献
94.
Raman spectra of the Li+, Na+, K+, NH+4, Mg2+, Ca2+, Sr2+, Ba2+, Pb2+ complexes of 12-crown-4 and also 12-crown-4 in various states are observed. The spectra of 12-crown-4 change remarkably by complex formation with cations. Normal vibration calculations of various conformations of 12-crown-4 are carried out. On the basis of the observed spectra and the results of the calculations, the conformation of 12-crown-4 in the Li+, Na+, K+, NH+4, Mg2+ complexes is found to have approximate D2d symmetry, while that in the Ca2+, Sr2+, Ba2+ complexes is found to have approximate C2V symmetry. 相似文献
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98.
Toshifumi Satoh Masaki Tamaki Yoshikazu Kitajyo Takahiro Maeda Hiroyuki Ishihara Tomoko Imai Harumi Kaga Toyoji Kakuchi 《Journal of polymer science. Part A, Polymer chemistry》2006,44(1):406-413
A novel biodegradable unimolecular reversed micelle consisting of a poly(L ‐lactide) (PLA) shell and a hyperbranched D ‐mannan (HBM) core, that is, a chestnut‐shaped polymer (PLA–HBM), was synthesized by the polymerization of L ‐lactide on HBM with 4‐(dimethylamino)pyridine (DMAP) as the catalyst. The obtained polymers were soluble in dimethyl sulfoxide, tetrahydrofuran, and chloroform but insoluble in H2O. The molecular weights of the PLA chain on PLA–HBM tended to increase with increasing polymerization time. The number of PLA chains on PLA–HBM could be controlled by the ratio of DMAP to the sugar unit in HBM. The obtained copolymer, PLA–HBM, acted as a unimolecular reversed micelle with an encapsulation ability toward the hydrophilic molecule. In addition, the entrapped hydrophilic molecules were slowly released from the core of PLA–HBM, and the release rate was accelerated by the breaking of the PLA chains of the shell when proteinase K as a hydrolase of PLA was used. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 406–413, 2006 相似文献
99.
In the paper, we show continuity of cone-convex set-valued maps by using nonconvex scalarization methods for sets. 相似文献
100.