Argonne National Laboratory

Science Highlights

Date Postedsort ascending
(a) Isosurface (30%) of the reconstructed amplitude superimposed with a model of the possible {111} and {100} crystal planes. The normal directions of two sets of crystalline planes {111} and {100} are marked by two kinds of arrows (fat and narrow), and the one (111) used for the measurement is marked in red. (b,c) are the top and bottom view of phase shift distribution pasted on the 30% isosurface plot. Three strain distinguished locations numerically labelled are chosen for quantitative measurement as a function of pressure. (d) 3D phase distribution at different slicing depths spaced apart by 20 nm steps from top to bottom of the crystal. The colour scale is used to show the relative phase shift and normalized to range [−π/4, π/4].To view a larger version of the image, click on it.
A high-pressure nanoimaging breakthrough

A team of researchers made a major breakthrough in measuring the structure of nanomaterials under extremely high pressures.

July 16, 2013
SRIM-2008 calculated implanted Xe concentration (at.%, solid lines) and accumulated damage (dpa, dashed lines). To view a larger version of the image, click on it.
Studying defects created by irradiating molybdenum crystals

In situ Transmission Electron Microscopy (TEM) studies of Xe implantations in pure single crystal Molybdenum were conducted to study irradiation damage and inert gas bubble formation and growth behaviors.

July 16, 2013
Dynamic trees can aid in performance tuning of scientific codes

Researchers have developed a data analysis tool that uses dynamic trees to rapidly determine which software and hardware tuning parameters best explain differences in code performance.

July 16, 2013
Ames Laboratory scientists discover new family of quasicrystals

Scientists at the U.S. Department of Energy’s (DOE) Ames Laboratory have discovered a new family of rare-earth quasicrystals using an algorithm they developed to help pinpoint them.

July 16, 2013
Synthesis of PFeTTPP. a) Molecular structure; b) simulated 3D stacking of PFeTTPP. Fe red, N blue, C light blue, S yellow; H not shown for clarity. To view a larger version of the image, click on it.
A new route to making high-efficiency, low-cost electrocatalysts

Researchers reported a new method of fabricating a highly efficient, “support-free” oxygen reduction catalyst for fuel cell application using an ultrahigh surface area polyporphyrin as precursor.

July 16, 2013
(A) Lattice structure of GdSi, viewed along the incommensurate antiferromagnetic wave vector (0, 0.483, 0.092) direction. (B) DC magnetic susceptibility measured along all three orthogonal axes shows two magnetic phase transitions at 53.0 and 54.7 K. (Inset) Susceptibility vs. temperature from 1.8 to 300 K. To view a larger version of the image, click on it.
Electronic interactions give rise to quantum phenomena in rare-earth magnets

Researchers studied a unique example of the nesting-driven spin density wave ground state in the rare-earth magnet GdSi that allowed them to explore the local and itinerant spin interaction.

July 16, 2013
Distribution of AEZs in the United States. To view a larger version of the image, click on it.
Land-use change and greenhouse gas emissions from corn and cellulosic ethanol

This paper investigates the effect of several key domestic lands carbon content modelling parameters on LUC GHG emissions.

July 16, 2013
TOP: cluster model of drug intercalated in between two Watson-Crick base-pairs connected by sugar puckers and phosphate groups. BOTTOM: neutral “wild-type” ellipticine, R equation image denote sites of groups permitted to mutate. To view a larger version of the image, click on it.
Machine-learning algorithm aims to accelerate materials discovery

A research team is developing an algorithm that combines quantum chemistry with machine learning (artificial intelligence) to enable atomistic simulations that predict the properties of new materials with unprecedented speed.

July 16, 2013
Current dependence of (a) non-linear amplication factor (1 + v2), and (b) integrated power at the three angles.
Motion of nanomagnet oscillators

Nanopillars consisting of two magnetic layers separated by an insulating or non-magnetic metal can exhibit oscillations: a constant current can make the magnetization in one layer precess with frequencies in the gigahertz range.

July 15, 2013
Figure 1: NDM-1 in complex with hydrolyzed ampicillin. Stereoview of the active site, with carbon atoms in the protein shown in cyan; those in the substrate are pink. Nitrogen atoms are blue, oxygen atoms are red, sulfur atoms are yellow, and zinc ions are magenta. An oriented water molecule (W) is gray. The Fo-Fc electron density around the substrate is contoured at 3σ. Dashed lines indicate key interactions between the protein and zinc ions. To view a larger version of the image, click on it.
Solving the catalytic pathway of antibiotic resistance

First identified in the bacteria Klebsiella pneumonia, a novel enzyme NDM-1 hydrolyzes and inactivates nearly all antibiotics with startling efficiency.

June 25, 2013