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.
New Insights into Nanoscale Deformation (4/20/2017) - A group of scientists used Laue x-ray microdiffraction at the ALS to probe plastic deformation mechanisms at the nanoscale. Their findings may overturn conventional theory and reshape our understanding of the mechanical behavior of a host of nanocrystalline metals.
3D Visualization of Leaves during Drought (4/18/2017) - The veins of living leaves at increasing levels of drought stress were visualized using x-ray microtomography. The results expand our view of leaf drought responses, beyond the traditional embolism-centric view, to a broader focus on the role of the surrounding living tissues in water movement during drought.
Bending the (β-Sheet) Curve to Shape Protein Cavities (4/14/2017) - Curved β sheets are basic building blocks of many protein cavities that, by serving as binding sites for other molecules, are essential to protein function. β-sheet curvature can now be controlled with atomic-level accuracy, opening the door to custom-designed sites capable of entirely new functions.
Ancient Ocean Temperatures Recorded in Mother-of-Pearl (3/27/2017) - Researchers have shown that the thickness of the nacre, or mother-of-pearl, that lines the insides of mollusk shells can be used to estimate ocean temperatures as far back as the early Jurassic period. X-ray studies of modern and ancient shells help establish the method's feasibility.
Mapping Catalytic Reactions on Single Nanoparticles (3/27/2017) - A new study confirms that structural defects and jagged surfaces at the edges of platinum and gold nanoparticles are key hot spots for chemical reactivity. The experiments should help researchers customize the structural properties of catalysts to make them more effective in fostering chemical reactions.
ARPES Overturns V2O3 Metal-to-Insulator Theory (3/27/2017) - Researchers report on angle-resolved photoemission spectroscopy (ARPES) measurements performed on the transition-metal oxide V2O3. The results overturn a decade-old theory about metal-to-insulator transitions in this material and provide a spectroscopic benchmark test for future models.
NCAA Drives Formation of Designed Proteins (3/26/2017) - A noncanonical amino-acid (NCAA) complex has been found to drive the self-assembly of a computationally designed protein. Bpy-ala, which is "noncanonical" because it's not among the 20 amino acids that occur naturally, has useful properties that could be used to generate novel photoactive proteins.
Ptychography of a Bacterium’s Inner Compass (3/14/2017) - Magnetotactic bacteria (MTB) synthesize chains of magnetic nanocrystals (magnetosomes) that interact with the Earth’s magnetic field like an inner compass needle, simplifying their search for optimum environments. Ptychographic spectra of magnetosomes from a marine MTB provides insight into how these inner compasses form.
GE Aviation Delves into Advanced Materials at the ALS (2/28/2017) - Developing ceramic matrix composites (CMCs) to replace the metal alloys traditionally used in jet engines has been a goal for the aviation industry for decades. For more than a year, GE Aviation has used the tomography capabilities at ALS Beamline 8.3.2 to gain insight into their CMC materials, guiding their engineering and design efforts.