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Solvent Extraction through the Lens of Advanced Modeling and Simulation
Published in Bruce A. Moyer, Ion Exchange and Solvent Extraction: Volume 23, 2019
Aurora E. Clark, Michael J. Servis, Zhu Liu, Ernesto Martinez-Baez, Jing Su, Enrique R. Batista, Ping Yang, Andrew Wildman, Torin Stetina, Xiaosong Li, Ken Newcomb, Edward J. Maginn, Jochen Autschbach, David A. Dixon
For higher extracted aqueous solute concentrations, the formation of large solute–extractant aggregates are commonly studied by combining experimental and simulation methods. Experimental X-ray and neutron scattering data are commonly used to validate simulation results, while simulation can provide detailed molecular descriptions of the ensemble of structures which result in a given measured scattering profile. Mu et al. demonstrated that SAXS data agree with simulations showing an absence of reverse-micelle like structures using Gibbs ensemble MC to generate the heavy and light organic phases which result under third-phase formation conditions.257 Combining MD simulation with X-ray and neutron scattering, Qiao et al. found that morphologies of diamide extractant aggregation with water in n-heptane is impacted by extractant alkyl tails and posited that certain resulting morphologies more readily accommodate extracted water.259 Simulation and corresponding SAXS and EXAFS data showed that spherical reverse-micelle-like aggregates of europium nitrate with a malonamide extractant expanded into long ellipsoids upon incorporation of water and nitric acid into the polar core, forming an extended hydrogen-bonding network of polar solutes.344
Sorption behavior of cesium and europium radionuclides onto nano-sized calcium silicate
Published in Particulate Science and Technology, 2020
H. S. Hassan, S. H. Kenawy, Gehan T. El-Bassyouni, Esmat M. A. Hamzawy, R. S. Hassan
Analytical reagents were used for the preparation of stoichiometric calcium silicate (CaSiO3, wollastonite) using calcium carbonate purchased from (El-Gomhorya Company for Chemicals. Egypt 99%) and silicon hydroxide gel purchased from (Fluka). Wollastonite based material was characterized using x-ray diffractometer [XRD, BRUKER, D8 ADVANCED Cu target, Germany] equipped with a rotating anode to observe any change in the phase behavior and crystallinity. A phase determination was carried out by means of standard ICDD (International Centre for Diffraction Data) card No. 01-076-0925 for wollastonite (CaSiO3). The (FT–IR) spectra of the wollastonite based adsorbents were recorded to analyze the functional groups using the KBr disc method (FT–IR, model FT/IR-6100 type A, USA). Nitrogen adsorption–desorption isotherms were determined with a high-speed gas sorption analyzer (NOVA 2000 series, Chromatic, UK) at 77 K. The Barrett–Emmett–Teller (BET) method was employed to determine the specific surface areas (SSA). The surface area measurement was studied using Nova 3200 autosorber (Quanta chrome corporation, USA). The surface area results showed 32/m2/g. The morphology and the size of the synthesized sample was designated through SEM coupled with energy-dispersive spectroscopy EDX, (SEM Model Quanta FEG 250, Holland) and transmission electron microscope (TEM) (JEM-HR-2100, Japan) to ensure the nano-size formation. Radisotopes of Cs and Eu were prepared by irradiating cesium and europium nitrate in Egyptian Research Reactor, ERR1.
Review on facile synthesis of cerium oxide nanoparticles and their biomedical applications
Published in Inorganic and Nano-Metal Chemistry, 2022
Suneela Kontham, Kiranmai Mandava, Sindhu Dosa, Faheem Uddin Mohd, Obaid Ahmed Mohammed, Aijaz Uddin Mohammad
For the first time, the synthesis of europium doped nanoceria was reported. Here the method involves the solution combustion synthesis (where the cerium nitrate hexahydrate, europium nitrate and urea acts precursors) and the water acts as the medium. To synthesize the rare nanocrystalline earth-doped ceria nano-powders, combustion methods was used, where a mixture of rare earth (RE) nitrates containing cerium and anhydrous citric acid was used (Figure 16). By using the scherrer’s formula, the size of the synthesized nanoceria was found to be 17–19.5 nm, where water is used as a medium.[6]
Energy transfer in and fluorescence studies of the Eu-Tb doped BPA-phen system
Published in Journal of Modern Optics, 2019
Guangbo Xie, Haibang Zhang, Zijun Zhang, Juntong Liu, Jingjing Zhang, Tingju Li
The present study used analytical-grade europium nitrate hexahydrate and terbium nitrate hexahydrate (Eu(NO3)3 6H2O and Tb(NO3)3 6H2O, respectively; Beijing HWRK Chemicals Co., China), BPA (Shanghai Macklin Biochemical Co., China), phen (Shanghai Zhanyun Chemical Co., China), PAN (Jilin Petrochemical Co., China), N,N-dimethylformamide (DMF; Tianjin Kermel Chemical Co., China) and ethanol with no further purification. The Eu(NO3)3 6H2O and Tb(NO3)3 6H2O were both of 99.99% purity.