Showing 1 - 11 of 11

"Visualizing the Hidden Half: Plant-Microbe Interactions in the Rhizosphere" Plant roots and the associated rhizosphere constitute a dynamic environment that fosters numerous intra- and interkingdom interactions, including metabolite exchange between plants and soil mediated by root exudates and the...

Aluminate salts precipitated from caustic alkaline solutions exhibit a correlation between the anionic speciation and the identity of the alkali cation in the precipitate, with the aluminate ions occurring either in monomeric (Al(OH)4–) or dimeric (Al2O(OH)62–) forms. The origin of this correlation...

To better understand the effects of solution chemistry on particle aggregation in the complex legacy tank wastes at the Hanford (WA) and Savannah River (SC) sites, we have performed a series of tumbler small- and ultra-small-angle neutron scattering experiments on 20 wt % solid slurries of...

The theoretical prediction of x-ray absorption spectra (XAS) has become commonplace in electronic structure theory. The ability to better model and understand L-edge spectra is of great interest in the study of transition metal complexes and a wide variety of solid state materials. However, until...

The recently developed real-time nuclear–electronic orbital (RT-NEO) approach provides an elegant framework for treating electrons and selected nuclei, typically protons, quantum mechanically in nonequilibrium dynamical processes. However, the RT-NEO approach neglects the motion of the other nuclei...

Understanding, controlling, and preventing aggregation of suspended particles is of fundamental importance in a number of scientific and industrial fields. There are several methods for analyzing aggregate morphology and aggregation kinetics, but small-angle scattering (SAS) techniques provide...

Predicting accurate nuclear magnetic resonance chemical shieldings relies upon cancellation of different types of errors between the theoretically calculated shielding constant of the analyte of interest and the reference. Often, the intrinsic error in computed shieldings due to basis sets...

In highly alkaline “water-in-salt” Na2O/Al2O3/H2O solutions where the monomeric Al(OH)4– anion dominates, isolation of transitional species that seed crystallization of sodium aluminate salt hydrates has been challenging. For example, discrimination of dimeric [for example, Al2O(OH)62–] species via...

Crystallization of Al3+-bearing solid phases from highly alkaline Na2O:Al2O3:H2O solutions commonly necessitates an Al3+ coordination change from tetrahedral to octahedral, but intermediate coordination states are often difficult to isolate. Here, a similar Al3+ coordination change process is...

Stanford Synchrotron Radiation Lightsource Experimental Station 14-3b is a bending magnet side station dedicated to X-Ray Imaging and Micro X-Ray Absorption Spectroscopy of biological, biomedical, materials, and geological samples. Station 14-3b is equipped with specialized instrumentation for XRF...

The Physical Electronics Instruments (PHI) Quantum 2000 X-Ray Photoelectron Spectrometer (XPS) is a unique Micro-Focused Scanning X-Ray system that uses a focused monochromatic aluminum K X-ray beam that can be varied in size from as small as 10 μm in diameter to approximately 200 μm. The beam can...