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Investigation of the iodate sorption mechanism by CoAl LDH through experiments and ab initio molecular dynamics simulations
Radioiodine released during the nuclear-fuel cycle constitutes a persistent radiological hazard. In this study, the IO 3 – uptake mechanism of CoAl LDH was resolved by combining pH-controlled sorption experiments, synchrotron XAFS, and DFT-based AIMD simulations. At pH close to 6, approximately 90% of IO 3 – was removed, and the equilibrium distribution coefficient reached about 1.7 × 10 4 mL g –1 . EXAFS analysis indicated an average iodine–oxygen bond length of 1.81 Å and a coordination number near 3, with the fit R-factor equal to 0.002. The simulations faithfully reproduced the experimental spectrum and revealed transient proton hopping events that generated metastable I–O–H species inside the interlayer, thereby confirming nitrate-to-iodate exchange as the controlling capture pathway. Atomic density profiles and radial distribution functions further showed that IO 3 – adopt an end-on orientation perpendicular to the hydroxide sheets, while water molecules mediate proton migration without disturbing the host lattice. In conclusion, the integrated experimental–computational evidence demonstrates that CoAl LDH can rapidly and selectively sequester IO 3 – under near-neutral conditions, offering atomic scale guidance for the rational engineering of layered sorbents for advanced radioactive-waste treatment.
Discrete dislocation dynamics simulations of dislocation-θ′ precipitate interaction in Al-Cu alloys
Not Available
Mechanical properties of silica glass predicted by a pair-wise potential in molecular dynamics simulations
Not Available
Ionic self-diffusion of Na[subscript 2]O-Al[subscript 2]O[subscript 3]-SiO[subscript 2] glasses from molecular dynamics simulations
Abstract not provided
Enabling molecular dynamics simulations of helium bubble formation in tritium-containing austenitic stainless steels: An Fe-Ni-Cr-H-He potential
Not Available
A critical review of the developments in molecular dynamics simulations to study femtosecond laser ablation
Not Available
Dislocation dynamics simulations of precipitation-strengthened Ni- and Co-based superalloys
Not Available
Electronic structure and tight-binding molecular dynamics simulations for calcium and strontium
Not Available
Radiation effect on BCC Fe nanoparticle with varying radiation energy by molecular dynamics simulation
Not Available
SHarD: A beam dynamics simulation code for dielectric laser accelerators based on spatial harmonic field expansion
In order to demonstrate acceleration of electrons to relativistic scales by an on chip dielectric laser accelerator (DLA), a ponderomotive focusing scheme capable of capturing and transporting electrons through nanometer-scale apertures over extended interaction lengths has been proposed. Here we present a Matlab-based numerical code (SHarD) utilizing a spatial harmonic expansion of the fields within the dielectric structure to simulate the evolution of the beam phase space distribution in this scheme. The code can be used to optimize key-parameters for the accelerator performance such as the final energy, transverse spot size evolution and total number of electrons accelerated through currently fabricated structures. Eventually, the simulation model will be applied to inform the phase mask profile to be added to a pulse front tilt drive laser pulse using a liquid crystal mask in the experimental setup being assembled at UCLA Pegasus Laboratory.
Threshold displacement energies and primary radiation damage in AlN from molecular dynamics simulations
Not provided.