12035-79-9Relevant articles and documents
Behavior of Pu(VI) and Np(VI) in malonate solutions
Bessonov,Krot,Grigor'ev
, p. 136 - 140 (2006)
Complexation of PuO22+ in solutions containing malonate anions C3H2O42- (L 2-) is studied by spectrophotometry. Mono- and bimalonate complexes are formed. The monomalonate complex was isolated as PuO2L· 3H2O. It is isostructural to UO2L·3H2O and forms rhombic crystals with the unit cell parameters a = 9.078(2), b = 7.526(2), and c = 6.2005(15) A, space group Pmn21. The electronic absorption spectrum of the monomalonate complex is characterized by a strong band at 843 nm. In malonate solutions, Pu(VI) is slowly reduced to the pentavalent state even in the cold. The reduction of Np(VI) is considerably faster and more sensitive to increasing temperature. Some kinetic features of the reduction are discussed. Pleiades Publishing, Inc., 2006.
Reduction of Pu(IV) and Np(VI) with carbohydrazide in nitric acid solution
Volk,Marchenko,Dvoeglazov,Alekseenko,Bychkov,Pavlyukevich,Bondin,D'Yachenko
, p. 143 - 148 (2012)
The reduction of Pu(IV) and Np(VI) with carbohydrazide (NH 2NH)2CO in 1-6 M HNO3 solutions was studied. The Pu(IV) reduction is described by a first-order rate equation with respect to Pu(IV). At [HNO3] ≥ 3 M, the reaction becomes reversible. The rate constants of the forward and reverse reactions were determined, and their activation energies were estimated. Neptunium(VI) is reduced to Np(V) at a high rate, whereas the subsequent reduction of Np(V) to Np(IV) is considerably slower and is catalyzed by Fe and Tc ions. The possibility of using carbohydrazide for stabilizing desired combinations of Pu and Np valence states was examined. Pleiades Publishing, Inc., 2012.
Unusual Metal-Organic Framework Topology and Radiation Resistance through Neptunyl Coordination Chemistry
Burns, Peter C.,Chen, Zhijie,Fairley, Melissa,Farha, Omar K.,Gilson, Sara E.,Hanna, Sylvia L.,Julien, Patrick,Laverne, Jay A.,Szymanowski, Jennifer E. S.
supporting information, p. 17354 - 17359 (2021/11/04)
A Np(V) neptunyl metal-organic framework (MOF) with rod-shaped secondary building units was synthesized, characterized, and irradiated with γrays. Single-crystal X-ray diffraction data revealed an anionic framework containing infinite helical chains of actinyl-actinyl interaction (AAI)-connected neptunyl ions linked together through tetratopic tetrahedral organic ligands (NSM). NSM exhibits an unprecedented net, demonstrating that AAIs may be exploited to give new MOFs and new topologies. To probe its radiation stability, we undertook the first irradiation study of a transuranic MOF and its organic linker building block using high doses of γrays. Diffraction and spectroscopic data demonstrated that the radiation resistance of NSM is greater than that of its linker building block alone. Approximately 6 MGy of irradiation begins to induce notable changes in the long- and short-range order of the framework, whereas 3 MGy of irradiation induces total X-ray amorphization and changes in the local vibrational bands of the linker building block.
Kinetics of reactions of Np and Pu ions with hydroxylamine derivatives: VIII. Reduction of Np(VI) with N,N-dibutylhydroxylamine
Koltunov, V. S.,Baranov, S. M.
, p. 236 - 241 (2008/10/08)
The rate of Np(VI) reduction with (C4H9)2NHOH(1+) in HC1O4 and HNO3 solutions is described by the equation -d[Np(VI)]/dt = k*[Np(VI)]*[(C4H9)2NHOH(1+)]/[H(1+)], where k = 15.6 +/- 1.1 min**-1 at 25.5°C and ionic strength μ = 2 in an HC1O4 solution and k = 16.0 +/- 1.0 min**-1 at 26.0°C in an HNO3 solution. The activation energy is E = 45.8 +/- 0.8 and 71.9 +/- 0.2 kJ*mol**-1, respectively. The reaction mechanismis discussed in comparison with that of the other Np(VI) reactions with disubstituted hydroxylamines.
