The Experts below are selected from a list of 300 Experts worldwide ranked by ideXlab platform

F Ruggieri - One of the best experts on this subject based on the ideXlab platform.

Xiangke Wang - One of the best experts on this subject based on the ideXlab platform.

  • plasma induced grafting of polyacrylamide on graphene oxide nanosheets for simultaneous removal of Radionuclides
    Physical Chemistry Chemical Physics, 2015
    Co-Authors: Wencheng Song, Xiangxue Wang, Qi Wang, Dadong Shao, Xiangke Wang
    Abstract:

    Polyacrylamide (PAM) grafted graphene oxide (denoted as PAM/GO) was synthesized by the plasma-induced polymerization technique and applied as an adsorbent for the simultaneous removal of Radionuclides from radioactive wastewater. The interactions of PAM/GO with the Radionuclides U(VI), Eu(III) and Co(II) were studied, along with their sorption kinetics. The results indicated that radionuclide sorption on PAM/GO was affected by the solution pH and ionic strength. The maximum sorption capacities of U(VI), Eu(III) and Co(II) on PAM/GO (0.698, 1.245 and 1.621 mmol g−1, respectively) at pH = 5.0 ± 0.1 and T = 295 K were much higher than those of Radionuclides on GO and other adsorbents. The thermodynamic data (ΔH0, ΔS0 and ΔG0) calculated from the temperature-dependent sorption isotherms suggested that the sorption of Radionuclides on PAM/GO was a spontaneous and endothermic process. These results indicate that PAM/GO is a promising material for the control of radionuclide pollution.

Michael Schoppner - One of the best experts on this subject based on the ideXlab platform.

Brit Salbu - One of the best experts on this subject based on the ideXlab platform.

  • Fractionation of radionuclide species in the environment.
    Journal of environmental radioactivity, 2009
    Co-Authors: Brit Salbu
    Abstract:

    Naturally occurring and artificially produced Radionuclides in the environment may be present in different physico-chemical forms (i.e., radionuclide species) varying in size (nominal molecular mass), charge properties and valence, oxidation state, structure and morphology, density, degree of complexation, etc. Low molecular mass (LMM) species are believed to be mobile and potentially bioavailable, while high molecular mass (HMM) species such as colloids, polymers, pseudocolloids and particles are considered inert. Due to time-dependent transformation processes such as mobilisation of radionuclide species from solid phases or interactions of mobile and reactive radionuclide species with components in soils and sediments, the original distribution of Radionuclides deposited in ecosystems will change over time. To assess the environmental impact from radionuclide contamination, information on radionuclide species deposited, interactions within affected ecosystems and the time-dependent distribution of radionuclide species influencing mobility and biological uptake is essential. The development of speciation techniques to characterize radionuclide species in waters, soils and sediments should therefore be essential for improving the prediction power of impact and risk assessment models. The present paper reviews available fractionation techniques which can be utilised for radionuclide speciation purposes.

Daniel I Kaplan - One of the best experts on this subject based on the ideXlab platform.

  • recent advances in the detection of specific natural organic compounds as carriers for Radionuclides in soil and water environments with examples of radioiodine and plutonium
    Journal of Environmental Radioactivity, 2017
    Co-Authors: Peter H Santschi, Saijin Zhang, K A Schwehr, Peng Lin, Chris M Yeager, Daniel I Kaplan
    Abstract:

    Abstract Among the key environmental factors influencing the fate and transport of Radionuclides in the environment is natural organic matter (NOM). While this has been known for decades, there still remains great uncertainty in predicting NOM-radionuclide interactions because of lack of understanding of radionuclide interactions with the specific organic moieties within NOM. Furthermore, radionuclide-NOM studies conducted using modelled organic compounds or elevated radionuclide concentrations provide compromised information related to true environmental conditions. Thus, sensitive techniques are required not only for the detection of Radionuclides, and their different species, at ambient and/or far-field concentrations, but also for potential trace organic compounds that are chemically binding these Radionuclides. GC-MS and AMS techniques developed in our lab are reviewed here that aim to assess how two Radionuclides, iodine and plutonium, form strong bonds with NOM by entirely different mechanisms; iodine tends to bind to aromatic functionalities, whereas plutonium binds to N-containing hydroxamate siderophores at ambient concentrations. While low-level measurements are a prerequisite for assessing iodine and plutonium migration at nuclear waste sites and as environmental tracers, it is necessary to determine their in-situ speciation, which ultimately controls their mobility and transport in natural environments. More importantly, advanced molecular-level instrumentation (e.g., nuclear magnetic resonance (NMR) and Fourier-transform ion cyclotron resonance coupled with electrospray ionization (ESI-FTICRMS) were applied to resolve either directly or indirectly the molecular environments in which the Radionuclides are associated with the NOM.