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The advances in computational actinide chemistry made in China are reviewed. Several areas relevant to chemistry of actinides in gas, liquid, and solid phases have been explored. However, we limit the scope to selected contributions in the chemistry of molecular actinide systems in gas and liquid phases. These studies may be classified into two categories: treatment of relativistic effects, which cover the development of two- and four-component Hamiltonians and the optimization of relativistic pseudopotentials, and the applications of theoretical methods in actinide chemistry. The applications include (1) the electronic structures of actinocene, noble gas complexes, An-C multiple bonding compounds, uranyl and its isoelectronic species, fluorides and oxides, molecular systems with metal-metal bonding in their isolated forms (U2, Pu2) and in fullerene (U2@C60), and the excited states of actinide complexes; (2) chemical reactions, including oxidation, hydrolysis of UF6, ligand exchange, reactivities of thorium oxo and sulfido metallocenes, CO2/CS2 functionalization promoted by trivalent uranium complex; and (3) migration of actinides in the environment. A future outlook is discussed. [ABSTRACT FROM AUTHOR]

A bioassay capable of monitoring occupational or environmental exposure to special nuclear materials would be a useful tool for nuclear nonproliferation programs. Hair and nail are potential biomonitors of exposure to U and Pu. A method is described to measure isotope ratios of ultra-trace concentrations of U and Pu in hair and nail samples. The method uses multiple extraction chromatography resins to separate U and Pu fractions from the sample matrix. The U recovery was quantitative while the Pu recovery ranged from 81% to 109%, with a U decontamination factor of 5×10(4). Following the separation (234)U/(238)U, (235)U/(238)U and (240)Pu/(239)Pu were measured in human hair and hair and nail samples using multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS). The human hair and nail samples had elevated ratios of (234)U/(238)U which could reflect exposure to naturally fractionated U., (Copyright © 2014 Elsevier B.V. All rights reserved.)