Protein Complex Shows Promise for Berkelium Separation (6/19/2017) - Scientists found that the element berkelium breaks form with its heavy element peers by taking on an extra positive charge when bound to a synthetic organic molecule. This property could help scientists develop better methods for handling and purifying nuclear materials.
New Evidence for a Water-Rich History on Mars (6/15/2017) - Mars may have been a wetter place than previously thought, according to experiments on lab-synthesized mineral samples serving as proxies for Martian meteorites. Shock experiments followed by x-ray diffraction studies showed how changes in the minerals could indicate a more water-rich history for the Red Planet.
A Systematic Approach to Customizing Cyclic Proteins (6/13/2017) - Proteins consisting of identical subunits arranged symmetrically around a central axis (cyclic homo-oligomers) play key roles in many biological processes. Researchers have now developed a systematic approach to their design and demonstrated its accuracy using protein crystallography and small-angle x-ray scattering.
Bacterial Symbiont Sequesters Arsenic and Barium in Sponges (5/30/2017) - Researchers used x-ray fluorescence, spectroscopy, and diffraction to study how populations of symbiotic bacteria can act as a detox organ in a host with no organs. The bacteria, members of the species Entotheonella, accumulate and mineralize large quantities of arsenic and barium in sponges.
APXPS Finds Carbonate Reversal at Liquid Interfaces (5/30/2017) - Aqueous carbonate systems are central to many processes essential to life, from the blood buffer system to the global carbon cycle. Using APXPS, researchers probed the concentration of carbonates near an interface, finding a surprising reversal in the expected abundances as a function of depth.
A Closer Look at a Working Platinum/Electrolyte Interface (5/24/2017) - Ambient-pressure studies of the interface between a platinum electrode and an alkaline electrolyte revealed the molecular-level chemistry, structure, and dynamics of the platinum surface as a function of applied potential, highlighting differences between thermodynamic predictions and the actual surface composition.
A Hollow Pyramid Unlocks Principles of Protein Architecture (5/22/2017) - Researchers have designed a hollow, pyramid-shaped protein with a controllable cavity size that could be useful in the capture and release of smaller compounds. The tools and techniques developed could be useful in analyzing and optimizing designed protein assemblies and understanding their behavior in solution.
Strain Turns Tin into a 3D Topological Dirac Semimetal (5/11/2017) - A small amount of compressive strain turns a nonmetallic form of tin into a 3D topological Dirac semimetal—a kind of "supermetal" with very high electron mobility. With its rich topological phase diagram, the material shows promise for both novel physics and eventual device applications.
Electronic Phase Separation and Dramatic Inverse Band Renormalization in the Mixed-Valence Cuprate LiCu2O2 (4/28/2017) - Angle-resolved photoemission spectroscopy was used to measure the electronic structure of LiCu2O2, a mixed-valence cuprate where planes of Cu(I) (3d10) ions are sandwiched between layers containing one-dimensional edge-sharing Cu(II) (3d9) chains.
Modulating Infrared Light with 2D Black Phosphorus (4/24/2017) - Two-dimensional materials represent a promising new frontier in the field of optoelectronics. Most progress so far, however, has been in the visible-light range. Now, at the ALS, researchers have measured the infrared transmission spectra of ultrathin samples of black phosphorus under an applied electric field.