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91.
A remarkable enhancement of the extraction of lanthanoids(Ⅲ)(Ln) with β-diketones in the presence of a Lewis base, so-called synergistic effects, would be caused by the adduct formation of the β-diketonates with the Lewis base. The trend of the variation of the adduct formation constants across the lanthanoid series may be different among β-diketones used. It has also been observed that the trend across lanthanoid series and also the values of the enthalpy change in the adduct formation of the 2-thenoyltrifluoroacetonates(TTA) with 1,10-phenanthroline(phen) are very similar to those with 2,25-bipyridyl(bpy), although the values of the adduct formation constants with the former are larger than those with the latter. 相似文献
92.
Kawashima Natsumi Kitazaki Tomoya Nogo Kosuke Nishiyama Akira Wada Kenji Ishimaru Ichiro 《Optical Review》2020,27(6):530-541
Optical Review - We propose a superimposing interferogram method to enhance the sensitivity and interference definition of spatial-phase-shift interferometers. The proposed method uses a multi-slit... 相似文献
93.
Iori Era Yasutaka Kitagawa Natsumi Yasuda Taigo Kamimura Naoka Amamizu Hiromasa Sato Keigo Cho Mitsutaka Okumura Masayoshi Nakano 《Molecules (Basel, Switzerland)》2021,26(20)
The effect of hydrogen bonds around the active site of Anabaena [2Fe-2S] ferredoxin (Fd) on a vertical ionization potential of the reduced state (IP(red)) is examined based on the density functional theory (DFT) calculations. The results indicate that a single hydrogen bond increases the relative stability of the reduced state, and shifts IP(red) to a reductive side by 0.31–0.33 eV, regardless of the attached sulfur atoms. In addition, the IP(red) value can be changed by the number of hydrogen bonds around the active site. The results also suggest that the redox potential of [2Fe-2S] Fd is controlled by the number of hydrogen bonds because IP(red) is considered to be a major factor in the redox potential. Furthermore, there is a possibility that the redox potentials of artificial iron-sulfur clusters can be finely controlled by the number of the hydrogen bonds attached to the sulfur atoms of the cluster. 相似文献
94.
Masayuki Kurokuzu Shinji Kitao Yasuhiro Kobayashi Makina Saito Ryo Masuda Takaya Mitsui Yoshitaka Yoda Makoto Seto 《Hyperfine Interactions》2014,226(1-3):687-691
The Mössbauer spectra of the 35.49 keV excited state of 125Te were observed in the energy domain using synchrotron radiation for the first time. The obtained isomer shifts and Debye temperature agree with previous experiments. These results show that this method will be applicable to various compounds. 相似文献
95.
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97.
Reaction of chiral 2-[(tributylstannyl)methyl]propenamides with aldehydes proceeded with 1,6-asymmetric induction to give, after hydrolysis, α,-methylene-γ-butyrolactones in enantiomeric excesses as high as 80%. 相似文献
98.
A general procedure has been developed for the synthesis of 3,4-epoxy-2-methylenealkanoic acid derivatives using dianion of N-phenyl-2-(phenylsulfonylmethyl)propenamide and aldehydes. 相似文献
99.
The crystallite orientation and lamellar deformation produced by hot-rolling in polyethylene have been investigated. In the lightly rolled stage, the [110]* axis of polyethylene crystals orientates in the plane perpendicular to the rolling direction and the c axis becomes aligned with the rolling direction. In the heavily rolled stage the a, b, and c axes coincide with the macroscopic directions in the sample. These orientational changes are interpreted in terms of a slip mechanism. Small-angle x-ray scattering (SAXS) investigations of hot-rolled polyethylene show the following. (1) There are two kinds of lamellar structures; one in which inclined lamellae give a four-point diagram in the SAXS photograph and another in which lamellar normals are oriented around the rolling direction even at the lightly rolled stage. The latter structure is attributed to the mechanism of unfolding and recrystallization. (2) The chain-fold length in the original structure remains unchanged in the lamellae up to a roll ratio of four although the apparent long period decreases. This is explained by inclination of polymer chains in the lamellae. Further rolling aligns the polymer chains with the rolling direction and the fold length decreases. 相似文献
100.