Dec. 06, 2013
X-rays transformed medicine a century ago by providing a noninvasive way to detect internal structures in the body. Still, they have limitations: X-rays cannot image the body's soft tissues, except with the use of contrast-enhancing agents that must be swallowed or injected, and their resolution is limited. But a new approach developed by researchers at MIT and Massachusetts General Hospital (MGH) could dramatically change that, enabling the most detailed images ever -including clear views of soft tissue without any need for contrast agents.
moreNov. 28, 2013
As features of modern electronics shrink, the demands of the spatial resolution of the characterization techniques increase. One family of potential building blocks for future devices is nanowires. We show how low-temperature cathodoluminescence can be used to study variations in the emission from two types of nanowires: Nanowires with a GaInAs segment in an otherwise GaAs core and radial InAs quantum wells on an InP core.
moreNov. 26, 2013
A new electron microscope invented at Michigan State University allows scientists to zoom in on the movements of atoms and molecules. Electron microscopes allow scientists to see the structure of microorganisms, cells, metals, crystals and other tiny structures that weren't visible with light microscopes. But while these images have allowed scientists to make great discoveries, the relationship between structure and function could only be estimated because of static images. In the 1990s, researchers added a fourth dimension - time - by using a laser to capture images of gaseous molecules as they were reacting.
moreOct. 08, 2013
Through a combination of transmission electron microscopy (TEM) and their own unique graphene liquid cell, researchers at the U.S. Department of Energy (DOE)'s Lawrence Berkeley National Laboratory (Berkeley Lab) have recorded the three-dimensional motion of DNA connected to gold nanocrystals (see movie). This is the first time TEM has been used for 3D dynamic imaging of so-called soft materials. The results were published in the journal Nano Letters.
moreOct. 05, 2013
The combination of ACOM-TEM with in situ straining inside a TEM enables direct imaging of the local crystal orientation at the nanoscale during straining of nanocrystalline metals and thus various deformation processes such as grain growth, twinning/detwinning and grain rotation can be distinguished in real space. A quantitative analysis of the crystal orientation changes observed by this new approach was used to study the deformation processes in nanocrystalline gold .
moreOct. 01, 2013
The world's sharpest X-ray beam shines at DESY. At the X-ray light source PETRA III, scientists from Göttingen generated a beam with a diameter of barely 5 nanometres - this is ten thousand times thinner than human hair. This fine beam of X-ray light allows focusing on smallest details. The research groups of Professor Tim Salditt from the Institute of X-ray Physics and of Professor Hans-Ulrich Krebs from the Institute of Materials Physics of the University of Göttingen published their work in the research journal Optics Express.
moreSep. 23, 2013
Mineralized human dental tissues were studied by advanced analytical transmission electron microscopy (TEM) techniques. The Ca/P and Mg/P at % ratios were determined employing energy dispersive X-ray spectroscopy (EDX) measurements. Significantly lower Ca/P and higher Mg/P at % ratios were measured in peritubular dentine compared to intertubular dentine, suggesting the incorporation of Mg in the hydroxylapatite lattice by substituting Ca. Improvement of TEM sample preparation is demonstrated.
moreSep. 19, 2013
Your smartphone now can see what the naked eye cannot: A single virus and bits of material less than one-thousandth of the width of a human hair. Aydogan Ozcan, a professor of electrical engineering and bioengineering at the UCLA Henry Samueli School of Engineering and Applied Science, and his team have created a portable smartphone attachment that can be used to perform sophisticated field testing to detect viruses and bacteria without the need for bulky and expensive microscopes and lab equipment. The device weighs less than half a pound.
moreAug. 26, 2013
Owing to their unique anisotropic structure and their extraordinary properties, carbon nanotubes (CNTs) have spurred great interest in a wide range of application, and more particularly in materials science where the CNT hybridizations with other materials offer significant advantages. CNTs grown on alumina micro-beads and silicon carbide micro-platelets are among the most promising multi-scale combinations due to their outstanding thermal, electrical and mechanical properties. By simply adjusting the synthesis parameters, one can significantly affect the final structure and thus the properties of the hybrids, opening up a large area to explore.
moreAug. 23, 2013
Mathematical modeling confirms that a nanometer-scale device that can concentrate light into a tiny spot improves optical sensing. Conventional lenses, made of shaped glass, are limited in how precisely they can redirect beams of incoming light and make them meet at a point. Now, a team led by Zhengtong Liu at the A*STAR Institute of High Performance Computing, Singapore, has proposed a novel approach to ‘superlens' systems that can surpass this classical limit of focusing light.