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1.
Summary Extraction of microamounts of cesium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of polyethylene glycol ligand PEG 400 (L) has been investigated. The equilibrium data have been explained
assuming that the complexes HL+and CsL+are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated
with water have been determined. 相似文献
2.
Summary From extraction experiments andg-activity measurements, the extraction constant corresponding to the 2Na+(aq)+SrL(nb)?2NaL+(nb)+Sr2+(aq) equilibrium taking place in the two-phase water-nitrobenzene system (L=benzo-15-crown-5; aq=aqueous phase, nb=nitrobenzene
phase) was evaluated as log Kex(2Na+,SrL)=1.0±0.1. Further, the stability constant of the benzo-15-crown-5-sodium complex in nitrobenzene saturated with water
was calculated for a temperature of 25 °C: log bnb(NaL+)=7.8±0.1. 相似文献
3.
P. Vaňura E. Makrlík V. Vobecký; 《Journal of Radioanalytical and Nuclear Chemistry》2003,256(1):171-172
A rapid separation for carrier-free 90Y in the aqueous phase of the water/nitrobenzene extraction system from an 90Y/90Sr generator was proposed. After two-stage extraction separation, chemical yield of 90Y in the final aqueous phase was roughly 80%, while 90Sr radionuclide impurity in this phase containing carrier-free 90Y was 10-6%. 相似文献
4.
E. Makrlík Z. Spíchal P. Vaňura P. Selucký 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(3):2135-2140
Extraction of microamounts of europium and americium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B?) in the presence of bis(diphenylphosphino)methane dioxide (DPPMDO, L) has been investigated. The equilibrium data have been explained assuming that the species $ {\text{HL}}^{ + } $ , $ {\text{HL}}_{2}^{ + } $ , $ {\text{ML}}_{2}^{3 + } $ , $ {\text{ML}}_{3}^{3 + } $ and $ {\text{ML}}_{4}^{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 $ {\text{EuL}}_{n}^{3 + } $ and $ {\text{AmL}}_{n}^{3 + } $ , where n = 2, 3 and L is DPPMDO, in water–saturated nitrobenzene are comparable, whereas in this medium the stability of the cationic species $ {\text{AmL}}_{4}^{3 + } $ (L = DPPMDO) is somewhat higher than that of $ {\text{EuL}}_{4}^{3 + } $ with the same ligand L. 相似文献
5.
Extraction distribution of microamounts of strontium in the water-CsCl-15-crown-5 (15C5,L)-nitrobenzene-cesium dicarbollylcobaltate system has been investigated. The equilibrium data have been explained assuming that the CsL+, CsL2
+ and SrL2
2+ complexes are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated with water have been determined. 相似文献
6.
P. Vaňura E. Makrlík M. Vobecký; 《Journal of Radioanalytical and Nuclear Chemistry》2003,257(2):437-440
Extraction of microamounts of strontium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of 12-crown-4 (12C4,L) has been investigated. The equilibrium data have been explained assuming that the complexes HL+, HL2
+, SrL2+ and SrL2
+2- are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated with water have been determined. 相似文献
7.
E. Makrlík P. Vaňura P. Selucký 《Journal of Radioanalytical and Nuclear Chemistry》2011,290(2):307-311
Solvent extraction of microamounts of cesium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of dodecaethylene glycol (DDEG, L) has been investigated. The equilibrium data have been explained assuming
that the species HL+, H2L2+, CsL+ and CsHL2+ (L = DDEG) are extracted into the organic phase. The values of extraction and stability constants of the complex species
in nitrobenzene saturated with water have been determined. 相似文献
8.
Summary From extraction experiments andg-activity measurements, the extraction constant corresponding to the Ag+(aq) + NaL+(nb)?AgL+(nb) + Na+(aq) equilibrium in the two-phase water-nitrobenzene system (L=valinomycin; aq=aqueous phase, nb=nitrobenzene phase) was evaluated
as log Kex(Ag+,NaL+)=-0.6±0.1. The stability constant of the valinomycin-silver complex in nitrobenzene saturated with water was calculated:
log bnb(AgL+)=4.6±0.1. The stability constants of complexes of some univalent cations with valinomycin were summarized and discussed. 相似文献
9.
E. Makrlík P. Vaňura Z. Spíchal P. Selucký 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(1):243-248
Extraction of microamounts of europium and americium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B?) in the presence of 1,3-bis(diphenylphosphino)propane dioxide (DPPPrDO, L) has been investigated. The equilibrium data have been explained assuming that the species $ {\text{HL}}^{ + } ,\,{\text{HL}}_{2}^{ + } ,\,{\text{ML}}^{3 + } \,{\text{and}}\,{\text{ML}}_{3}^{3 + } $ HL + , HL 2 + , ML 3 + and ML 3 3 + (M3+ = Eu3+, Am3+) are extracted into the organic phase. The values of extraction and stability constants of the complex species in nitrobenzene saturated with water have been determined. It was found that the stability constants of the corresponding complexes $ {\text{EuL}}_{n}^{ 3+ } \,{\text{and}}\,{\text{AmL}}_{n}^{ 3+ } , $ EuL n 3 + and AmL n 3 + , where n = 1, 3 and L is DPPPrDO, in water-saturated nitrobenzene are comparable. 相似文献
10.
Moakes G Daemen LL Gelbaum LT Leisen J Marecek V Janata J 《The journal of physical chemistry. B》2007,111(25):7312-7317
The effect of lithium ion on the ordering of water in water-saturated nitrobenzene has been probed by 2H NMR, diffusion ordered spectroscopy and neutron scattering. It was shown that increased water concentration in LiClO4/wet nitrobenzene results in the formation of a metastable solvatomer with mixed water and nitrobenzene character, Li+(W/NB). This species is shown to decay over hours to two solvatomers, one dominated by nitrobenzene Li+(NB) and the other dominated by water Li+(W). To confirm the assignment of these solvation states, diffusion ordered deuterium NMR spectroscopy has been used to elucidate the hydrodynamic radii of these solvatomers. Neutron scattering yields vibrational spectroscopy information that shows how addition of lithium to the nitrobenzene/water system results in relatively slow self-organization of the water environment (hours). 相似文献
11.
Summary Extraction of microamounts of yttrium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of benzo-15-crown-5 (B15C5,L) has been investigated. The equilibrium data have been explained assuming that
the complexes HL+, HL, YL3+, YL and YH-1L are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated
with water have been determined. 相似文献
12.
E. Makrlík P. Vaňura P. Selucky Z. Spíchal 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(1):13-18
Extraction of microamounts of europium and americium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of 1,2-(diphenylphosphino)ethane dioxide (DPPEtDO, L) has been investigated. The equilibrium data have been
explained assuming that the species HL+, HL2
+, ML2
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, 4 and L is DPPEtDO, in water-saturated nitrobenzene are comparable. 相似文献
13.
E. Makrlík 《Journal of Radioanalytical and Nuclear Chemistry》2002,253(2):327-329
Extraction of microamounts of barium by a nitrobenzene solution of ammonium dicarbollylcobaltate (NH4
+B-) in the presence of 15-crown-5(15C5,L) has been investigated. The equilibrium data have been explained assuming that the complexes NH4L+, NH4L2
+ and BaL2
2+ are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated with water have been determined. 相似文献
14.
From extraction experiments and γ-activity measurements, the exchange extraction constants corresponding to the general equilibrium $ {\text{M}}^{ + } \left( {\text{aq}} \right) \, + {\mathbf{1}}\cdot{\text{Na}}^{ + } \left( {\text{nb}} \right) \Leftrightarrow {\mathbf{1}}\cdot{\text{M}}^{ + } \left( {\text{nb}} \right) \, + {\text{Na}}^{ + } \left( {\text{aq}} \right) $ taking place in the two-phase water–nitrobenzene system $ \begin{gathered} ({\text{M}}^{ + } = {\text{ Li}}^{ + } ,{\text{ K}}^{ + } ,{\text{ Rb}}^{ + } ,{\text{ Cs}}^{ + } ,{\text{ H}}_{ 3} {\text{O}}^{ + } ,{\text{NH}}_{4}^{ + }, {\text{ Ag}}^{ + } ,{\text{ Tl}}^{ + } ;{\mathbf{1}} \\ = {\text{ nonactin}};{\text{ aq }} = {\text{ aqueous phase}},{\text{ nb }} = {\text{nitrobenzene phase}}) \\ \end{gathered} $ were determined. Moreover, the stability constants of the 1·M+ complexes in water-saturated nitrobenzene were calculated; they were found to increase in the series of $ {\text{Cs}}^{ + } < {\text{ Rb}}^{ + } < {\text{ H}}_{ 3} {\text{O}}^{ + } ,{\text{ Ag}}^{ + } < {\text{ Tl}}^{ + } < {\text{ Li}}^{ + } < {\text{ K}}^{ + } < {\text{NH}}_{4}^{ + } $ . 相似文献
15.
E. Makrlík P. Vaňura P. Selucký J. Hálová 《Journal of Radioanalytical and Nuclear Chemistry》2007,274(3):625-629
Extraction of microamounts of strontium and barium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−1) in the presence of benzo-18-crown-6 (B18C6, L) has been investigated. The equilibrium data been explained assuming that
the complexes HL+, ML2+, ML22+ and MHL23+ (M2+ = Sr2+, Ba2+) are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated
with water have been determined. 相似文献
16.
P. Vaňura E. Makrlík Z. Valentová 《Journal of Radioanalytical and Nuclear Chemistry》2002,253(1):157-159
The extraction of cesium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of Slovafol 909 (p-nonylphenylnonaethylene glycol, L) has been investigated. The equilibrium data have been explained assuming that the complexes HL+, HL2
+, CsL+ and CsL2
+ are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated with water have been determined. 相似文献
17.
E. Makrlík P. Vaňura P. Selucký 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(3):2215-2220
Solvent extraction of microamounts of calcium and strontium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B?) in the presence of dodecaethylene glycol (DDEG, L) has been investigated. The equilibrium data have been explained assuming that the species HL+, H2L2+, ML2+ and MHL3+ (M2+ = Ca2+, Sr2+; L = DDEG) are extracted into the organic phase. The values of extraction and stability constants of the complex species in nitrobenzene saturated with water have been determined. It was found that in this nitrobenzene medium, the stability constant of the SrL2+ complex is somewhat higher than that of CaL2+. 相似文献
18.
The phase transfer mechanism of 18-molybdophosphate anion at the water/nitrobenzene interface has been investigated by chronopotentiometry with cyclic linear current-scanning (CLC) and cyclic voltammetry (CV). The transfer species is 18-molybdophosphtae anion with a charge number of 4, H2[P2Mo18O62]4-. The transfer process is controlled by diffusion at a slow polarization rate and considerably influenced by pH of the aqueous phase. The stable forms and pH range of the heteropoly anion in the aqueous solution can be directly confirmed through voltammetric behavior. The theoretical analysis of the relationship between the transfer potential and solution pH is identical to the experimental results. The linear concentration relationship with the transfer peak current is suggested to be used in the determination of heteropoly acids (salts). 相似文献
19.
Individual extraction constants of some dicarbollylcobaltate anions in the water-nitrobenzene system
E. Makrlík J. Rais K. Baše J. Plešek P. Vaňura 《Journal of Radioanalytical and Nuclear Chemistry》1995,198(2):359-365
Individual extraction constants of nine dicarbollylcobaltate anions in the two-phase water-nitrobenzene system were determined radiometrically assuming that the changes of Gibbs energy of the transfer of the tetraphenylarsonium cation, Ph4As+, and of the tetraphenylborate anion, BPh
4
–
, from the aqueous into the nitrobenzene phase are equal. The constants obtained by this method were correlated with Hansch's constants of hydrophobity. 相似文献
20.
E. Makrlík P. Vaňura P. Selucký 《Journal of Radioanalytical and Nuclear Chemistry》2006,269(1):209-211
Summary Extraction of microamounts of calcium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of Slovafol 909 (L) has been investigated. The equilibrium data have been explained assuming that the complexes
HL+, HL, CaL2+ and CaL are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene
saturated with water have been determined. 相似文献