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61.
Actinide(III), (IV), (V) and (VI) ions were extracted by N,N-dimethyl-N,N-dihexyl-3-oxapentanediamide (DMDHOPDA) and thenoyltrifluoroacetone (HTTA). The extraction behaviors suggested the possibility of the mutual separation, and the convenient separation method of actinide ions (III), (IV), (V) and (VI) without reducing and oxidizing agents was studied. Th(IV) was extracted from the aqueous phase by HTTA (5 mM in toluene) in the first step. The Am(III) and U(VI) ions can be extracted by 1 and 20 mM DMDHOPDA in toluene, and the Np(V) ion can be extracted into nitrobenzene with 100 mM DMDHOPDA in the last step. The residual activities in the aqueous phase were much lower than the initial activities. These activities in the fractions were confirmed by the gamma- and the alpha-spectrometry. The one-through and rough separation is advanced, and in case of the fine isolation of actinide elements, each fraction should be purified in more detail. 相似文献
62.
63.
N,N-dimethyl-N,N-dihexyl-3-oxapentanediamide, DMDHOPDA, N,N-dihexyl-3-thiopentanediamide, DHTPDA and N,N-dihexyl-3-oxapentanediamide, DHOPDA were synthesized and tested for the synergistic extraction of Eu3+, Th4+, UO
2
2+
, NpO
2
+
and Am3+ with thenoyltrifluoroacetone (HTTA). Although Eu3+, Th4+, UO
2
2+
and Am3+ were not extracted by DHTPDA or DHOPDA alone, they were extracted synergistically when combined with HTTA. Analysis of the dependency of extraction on pH and extractant concentration indicated that the dominant extracted species were Eu(TTA)3(A), Th(TTA)3(A)(X), UO2(TTA)2(A) and Am(TTA)3(A) (where A is diamide, and X is chloroacetate or ClO
4
–
). 相似文献
64.
Kyoji Tsubakiyama Togoro Matsuo Takashi Sasaki Kenzo Yoshida Takashi Fujimura Kunio Araki 《Journal of polymer science. Part A, Polymer chemistry》1979,17(1):173-184
γ-Ray-induced polymerizations of ferrocenylmethyl methacrylate (FMMA) in crystalline and amorphous states were investigated with kinetical and ESR methods. In the crystalline state the polymerization of FMMA proceeded slowly and gave low-molecular-weight polymers, whereas in the amorphous state it proceeded rapidly and gave polymers of much higher molecular weight. Molecular weight distributions of these polymers were binodal. The temperature dependence and the dose-rate dependence of the polymerization rates were different between the two states. Wide-line nuclear magnetic resonance (NMR) spectra of the amorphous monomer suggested that the polymerization proceeded in a supercooled state. Electron spin resonance (ESR) spectra of γ-irradiated FMMA and 1,1′-ferrocenyl-di(methyl methacrylate) showed that ferrocene radicals and methacrylic radicals were formed simultaneously at low temperature; with increasing temperature the former radicals disappeared, whereas the latter changed into growing chain radicals. The yields of radicals were relatively low; this means that ferrocene groups in the monomers behave as a radiation energy absorber. 相似文献
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