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1.
E. Makrlík P. Vaňura P. Selucký V. A. Babain I. V. Smirnov 《Journal of Radioanalytical and Nuclear Chemistry》2009,279(3):743-747
Extraction of microamounts of europium and americium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of N,N,N′,N′-tetraethyl-2,6-dipicolinamide (TEtDPA, L) has been investigated. The equilibrium data have
been explained assuming that the cations HL+, HL23+, ML23+ and ML33+ (M3+ = Eu3+, Am3+) are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated
with water have been determined. It has been found that the stability constants of the corresponding complexes EuL
n,org3+ and AmL
n,org3+, where n = 2, 3 and L is TEtDPA, in the mentioned medium are comparable. 相似文献
2.
E. Makrlík P. Vaňura P. Selucky V. A. Babain I. V. Smirnov 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(3):839-844
Extraction of microamounts of europium and americium by a phenyltrifluoromethyl sulfone (FS 13) solution of hydrogen dicarbollylcobaltate
(H+B−) in the presence of N,N,N′,N′-tetraethyl-2,6-dipicolinamide (TEtDPA, L) has been investigated. The equilibrium data have been explained assuming that the
species HL+,
\textHL 2 + , {\text{HL}}_{ 2}^{ + } ,
\textML23 + {\text{ML}_{2}^{3 +}} and
\textML 3 3+ {\text{ML}_{ 3}^{ 3+}} (M3+ = Eu3+, Am3+) are extracted into the organic phase. The values of extraction and stability constants of the cationic complex species in
FS 13 saturated with water have been determined. It was found that the stability constants of the corresponding complexes
\textEuLn 3+ {\text{EuL}}_{n}^{ 3+ } and
\textAmLn 3+ {\text{AmL}}_{n}^{ 3+ }, where n = 2, 3 and L is TEtDPA, in the mentioned FS 13 medium are comparable. 相似文献
3.
E. Makrlík P. Vaňura P. Selucký 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(3):571-575
Extraction of microamounts of europium and americium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of tetraisopropyl methylene diphosphonate [T(iPr)MDP, L] has been investigated. The equilibrium data have
been explained assuming that the complexes HL+, HL2
+, ML2
3+, ML3
3+ and ML4
3+ (M3+ = Eu3+, Am3+) are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated
with water have been determined. It was found that the stability constants of the corresponding complexes EuL
n
3+ and AmL
n
3+, where n = 2, 3, 4 and L is T(iPr)MDP, in water-saturated nitrobenzene are comparable. 相似文献
4.
H. B. Yang E. H. Lee J. K. Lim D. Y. Chung K. W. Kim 《Journal of Radioanalytical and Nuclear Chemistry》2009,280(3):495-502
The extraction of Am(III) and Eu(III) using a γ-pre-irradiated N,N′-dimethyl-N,N′-dibutyltetradecyl malonamide (DMDBTDMA)
modified with N,N′-dihexyloctanamide (DHOA) in n-dodecane (NDD) at 4.5M HNO3 has been studied as a function of the absorbed dose up to 2×106 Gray. The distribution ratios of Am(III) and Eu(III) were almost constant until a dose of 1×105 Gray and then they decreased gradually up to a dose of 2×106 Gray. The decrease of the distribution ratios of Am(III) and Eu(III) are due to the decreasing concentration of the DMDBTDMA
by a γ-pre-irradiation and these results were supported by a determination of the DMDBTDMA concentration with a gas chromatography
method. The distribution ratios of Am(III), Eu(III), Ce, Nd and Y with γ-pre-irradiated (DMDBTDMA-DHOA)/NDD have also been
studied as a function of the nitric acid concentration and the extraction temperature. 相似文献
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6.
Yang Xing-Lu Bao Bo-Rong Zhou Fang Cao Wei-Guo Li Yu-Lan 《Journal of Radioanalytical and Nuclear Chemistry》2001,250(3):573-575
A novel extractant, N, N-didecanoylpiperazine (DDPEZ), was synthesized for the first time. The extraction of U(VI) by DDPEZ from aqueous nitric acid media in carbon tetrachloride has been studied. The dependence of extraction distribution ratio on concentration of aqueous nitric acid, extractant, salting-out agent and temperature was investigated and the enthalpy of the extraction was calculated. 相似文献
7.
E. Makrlík P. Vaňura P. Selucky V. A. Babain I. V. Smirnov 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(1):233-238
Extraction of microamounts of calcium and strontium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of N,N,N′,N′-tetraisobutyl-2,6-dipicolinamide [T(iBu)DPA, L] has been investigated. The equilibrium data have been explained assuming
that the species HL+, HL2
+, CaL2
2+, SrL2
2+ and SrL3
2+ are extracted into the organic phase. The values of extraction and stability constants of the cationic complexes in nitrobenzene
saturated with water have been determined. 相似文献
8.
Wei Zheng Lu Chuan Zhou Yu Jiao Caishan Zhang Meng Hou Hongguo Gao Yang Tian Guoxin 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(2):875-884
Journal of Radioanalytical and Nuclear Chemistry - The extraction behavior and separation performance of Re(VII) and U(VI) from the nitric acid medium were studied respectively, in which an... 相似文献
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Yang Xing-Cun Bao Bo-Rong Cao Wei-Gou Sun Guo-Xin Li Zhen 《Journal of Radioanalytical and Nuclear Chemistry》2001,250(3):559-561
A novel extractant, N,N-dilauroylpiperazine (DLPEZ), was synthesized for the first time. The extraction of uranium(VI) with the novel extractant in carbon tetrachloride from aqueous nitric acid media has been studied. The dependence of extraction distribution ratio on the concentration of aqueous nitric acid, extractant, salting-out agent and temperature was investigated and the enthalpy of the extraction was determined. 相似文献
13.
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
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N,N'-bis-(α-methylsalicylidene)-2,2-dimethyl-1,3-propanediimine (SBTD) modified silica gel was prepared and used as sorbent for solid phase extraction of Cr(III) ions from aqueous solution. This sorbent showed a high sorption affinity for Cr(III) while recovery of Cr(VI) was very low. The analyte ion retained on the column was eluted with 1 mol L(-1) HNO(3). The chromium ion in the eluent was determined by graphite furnace atomic absorption spectrometry. The effects of different parameters such as pH, eluent type and volume, Schiff's base concentration, sample and eluent flow rate, interfering ions and adsorbent amount were investigated. 相似文献
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Emanuel Makrlík Ji?í Dybal Ji?ina ?vor?íková Jan Budka Petr Vaňura 《Monatshefte für Chemie / Chemical Monthly》2010,287(1):507-510
Abstract
From extraction experiments in the two-phase water/nitrobenzene system, the stability constant of the silver ionophore IV (i.e., 5,11,17,23-tetra-tert-butyl-25,27-bis[2-(methylthio)ethoxy]calix[4]arene)–Ag+ complex in nitrobenzene saturated with water was determined. Furthermore, the most probable structure of the resulting complex was derived by means of density functional level of theory calculations. 相似文献18.
Y. -Sh. Wang G. -X. Sun B. -R. Bao S. -X. Sun 《Journal of Radioanalytical and Nuclear Chemistry》1997,218(1):119-121
The results of monitoring of85Kr volume activity in ground-level air of Prague over the period 1989–1995 are summariyed. Seasonal dependence with a maximum in late spring and summer months and a gradual increase of85Kr concentration in the atmosphere were observed. Linear approximation of long-term trend in the period 1983–1995 gives the growth rate of 35 mBq·m–3 per year. Exponential approximation provides an inter-year growth by 3.7% The measured values were compared to the prognosis of85Kr contamination development of the atmosphere from the early 1980s. They were found to be near to the low estimate of the assumed development. 相似文献
19.
《Journal of Coordination Chemistry》2012,65(11):1820-1826
Mononuclear O,O-coordinated complexes K2(MLCl2) M = Zn(II), Cd(II) and dinuclear complexes (MZnLCl2R2)x along with dinuclear N,N-coordinated complexes (M′ZnH2LCl2R2)y (where M = Zn(II), Cd(II), Hg(II) and M′ = M and Sn(IV); R = Cl, CH3; x = 0, ?2; y = 0, +2) of N′-1-,N′-2-dihydroxy-N-1-,N-2-dipyridin-2-ylethanedimidamide (H2L) have been prepared. All complexes have been characterized by 1H NMR, IR, EI-mass spectroscopy and elemental microanalysis. These results are in agreement with our prediction for structures of mono and dinuclear complexes of H2L and L?2 with Zn(II) in the gas phase by theoretical studies. 相似文献
20.
《Journal of Coordination Chemistry》2012,65(20):3637-3651
The potentially tridentate N,N′,O-donor N-trans-(2′-hydroxycyclohexyl)-2-aminomethylpyridine (1) forms ML2 complexes with M(II)?=?Cu, Ni, and Zn. X-ray crystal structures of the isostructural Ni(II) and Zn(II) complexes confirm bis-tridentate coordination in significantly distorted octahedral geometries as the all-cis facial isomer. Structural comparisons with the previously reported all-trans facial Cu(II) and cis,cis,trans(Npy) facial Co(III) complexes are presented. Protonation constants for 1 and stability constants with Cu(II), Ni(II), and Zn(II) are reported, with both ML and ML2 species defined. The trend for ML (log K 1 values for Cu, Ni, and Zn of 8.3, 6.9, and 5.3, respectively) is conventional. Protonation and stability constants with Cu(II) for N,N-bis(2-pyridylmethyl)amine (2) were also defined. The log K 1 value measured for 2 of 7.4 is very similar to that found for 1 of 8.3, despite the marked difference in the third donor group; it appears that the third donor of the tridentate ligand generally binds only poorly to Jahn–Teller elongated Cu(II) in solution. 相似文献