Role of H in Solvent Extraction of Am(III) and Eu(III) Using a Polydentate Bipyridine N-,O-Donor Ligand: Chemical Equilibrium States and Kinetic Aspects.

In this work, the influence of protonation on the kinetics and thermodynamics of extraction of the Am/Eu pair using N-heterocyclic dicarboxylic acid diamide ,'-diethyl-,'-bis(4-ethylphenyl)-[2,2'-bipyridine]-6,6'-dicarboxamide () was investigated. The extraction efficiency of the ligand did not decrease, even at a nitric acid concentration 4 times higher than that of the ligand in the organic phase. X-ray diffraction analysis established that protonation leads to the preorganization of the ligand due to the reversal of bipyridyl rings into the binding conformation when both nitrogen atoms are turned to one side.

Experimental and Theoretical X-ray Absorption Near Edge Structure Study of UO Systems at the U L Edge.

Uranium forms a large number of oxides and its electronic state in them is of great fundamental interest. We employ X-ray absorption spectroscopy at the U L edge to differentiate between mixed oxide phases in uranium compounds. By combining experimental XANES spectra with theoretical modeling using the FEFF code, we analyze five uranium oxides: UO, UO, UO, UO, and UO.

Coordination of Fluorine-Substituted 1,10-Phenanthroline Diphosphonates with Americium(III) and Lanthanides(III): Solvent Extraction, Complexation, XRD, and Theoretical Study.

Hybrid N,O-donor ligands based on 1,10-phenanthroline are a promising class of compounds for processing high-level waste. Here, we synthesized novel phenanthroline-based diphosphonates containing electron-withdrawing fluorine atoms in alkyl substituents. We studied their extraction properties for Am(III) and, for the first time, for the entire series of lanthanides(III).

Remarkable Effect of Stereoisomerism on the Am(III)/Ln(III) Solvent Extraction. New Ligands for Highly Efficient Separation of Americium.

Two novel 1,10-phenanthroline-2,9-diamide ligands were constructed on the basis of 2-phenylpyrrolidine and obtained as pure diastereomers. These ligands demonstrated advanced properties in liquid-liquid extraction tests. They revealed high efficiency of americium(III) extraction alongside with the record values of selectivity in the separation of americium from light lanthanides from strongly acidic media.

Simultaneous mesoscopic measurement and manipulation of mouse cortical activity.

Dynamics of activity across the cerebral cortex at the mesoscopic scale - coordinated fluctuations of local populations of neurons - are essential to perception and cognition and relevant to computations like sensorimotor integration and goal-directed task engagement. However, understanding direct causal links between population dynamics and behavior requires the ability to manipulate mesoscale activity and observe the effect of manipulation across multiple brain regions simultaneously. Here, we develop a novel system enabling simultaneous recording and manipulation of activity across the dorsal cortex of awake mice, compatible with large-scale electrophysiology from any region across the brain.