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The suitability of perrhenate (Re(VII)) to act as an analog for pertechnetate (Tc(VII)) was tested using solvent extraction and the carrier/tracer systems 99Tc(VII)/99mTc(VII) and 185/187Re/186/188Re(VII). Perrhenate is often used as a non-radioactive analogue of pertechnetate, but scarce data is available for the comparison of these metals for liquid-liquid extraction applications. Results show that neither Tc(VII) nor Re(VII) extraction is influenced by pH in the 2–8 range. The anion extractant also separates electrolyte anions, with increasing extraction following the order Cl− < NO3− ≪ ClO4−, resulting in a decreased Tc(VII) and Re(VII) extraction in presence of salt. In particular, the extraction of Re and Tc is suppressed in presence of NaCl at concentrations higher than 1 mM. While Tc extraction is larger than that of Re in absence of electrolyte, they are statistically identical in presence of enough electrolyte. Furthermore, tetraphenylphosphonium chloride (Ph4PCl) is a stronger extractant than iodonitrotetrazolium chloride (INT). [ABSTRACT FROM AUTHOR]

The reactions of simple oxides or halides of trivalent lanthanides and actinides or bismuth with boric acid in the ionic liquid 1-butyl-3-methylimidazolium chloride at 150 °C result in the formation and crystallization of a series of isomorphous tetranuclear borate clusters with the general formula M4B22O36(OH)6(H2O)13 (M = La, Ce, Pr, Nd, Sm, Eu, Gd, Pu, and Bi). These clusters do not assemble with trivalent cations smaller than Gd3+, suggesting that the formation of the clusters is dictated by the size of the metal ion. The cations are found in cavities along the periphery of a cage assembled from the corner- and edge-sharing interactions of BO3 triangles and BO4 tetrahedra, yielding a complex chiral cluster. Both enantiomers cocrystallize. The metal ions are nonacoordinate, and their geometries are best described as distorted tridiminished icosahedra. This coordination environment is new for both Pu3+ and Bi3+. In addition to detailed structural information, UV/vis-NIR absorption and photoluminescence spectra are also provided. [ABSTRACT FROM AUTHOR]

Fournew uranyl phosphonate compounds have been synthesized viaionothermal flux in the ionic liquids 1-butyl-3-methylimidazoliumchloride ([Bmim][Cl]) and 1-ethyl-3-methylimidazolium bromide ([Emim][Br]).[C8H15N2][UO2(C6H5PO3H)(C6H5PO3)] ([Bmim][UPhPO]), [C8H15N2]2[(UO2)4(C6H5PO3)3Cl4] ([Bmim][UPhPOCl]), [C8H15N2][UO2(HO3P(CH2)3PO3)] (α-[Bmim][UC3DPO]), and [C6H11N2]2[(UO2)2(p-C6H4(PO3H)2)3]·2H2O ([Emim][UPhDPO])form one-dimensional chains, two-dimensional sheets, or three-dimensionalframeworks. For comparison, analogous reactions were carried out hydrothermally,which lead to one new framework structure, [C8H15N2]2[(UO2)5(HO3P(CH2)3PO3)4] (β-[Bmim][UC3DPO]), and one previously characterized tubular uranyl phosphonate. Itwas found that the structure is equally dictated by the choice offlux method, the choice of ligand, and the choice of ionic liquid. [ABSTRACT FROM AUTHOR]

Uranium-230 (t 1/2  = 20.8 d) is an alpha-emitting radionuclide that has potential application in targeted alpha therapy (TAT) of cancer. Its parent isotope 230 Pa (t 1/2  = 17.4 d), can be produced by proton irradiation of thorium metal targets. Preliminary 230 Pa production runs were performed at the Los Alamos National Laboratory Isotope Production Facility (LANL-IPF) using thin thorium metal targets and a proton beam energy of 15-30 MeV, followed by radiochemical separation of 230 Pa from the irradiated target matrix. The measured 230 Pa production yields were found to exceed the predicted values in most of the experiments that were performed. This data will inform further production efforts for providing 230 Pa/ 230 U for clinical trials., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 Elsevier Ltd. All rights reserved.)