By Andrew Myers
You’ve felt the heat before — the smartphone that warms while running a navigation app or the laptop that gets too hot for your lap.
The heat produced by electronic devices does more than annoy users. Heat-induced voids and cracking can cause chips and circuits to fail.
Schematic of the experimental thermal transistor. A slice of molybdenum disulfide (MoS2) sits on a piece of silicon dioxide, bathed in a solution of lithium ions. (Sood et al, Nature Communications)
Josh Hihath is trying to fuse biology and electrical engineering and to build new types of electronic memory based on DNA. Hihath, professor in the UC Davis Department of Electrical and Computer Engineering, is principal investigator of a grant just funded by the Semiconductor Synthetic Biology for Information Processing and Storage Technologies (SemiSynBio) program. SemiSynBio is a partnership between the National Science Foundation and the Semiconductor Research Corporation.
Researchers at UC Davis, University of Washington and Emory University hope to use self-assembling DNA molecules to build a “DNA-ROM” that can store digital information. (Josh Hihath/Yonggang Ke)
UC Davis project scientist Gong Chen (right) and coauthor Andres Schmid of Lawrence Berkeley Lab with the SPLEEM instrument used for imaging magnetic fields inside materials. Photo by Roy Kaltschmidt/LBL.
Tiny swirling textures in the magnetic fields within layered materials could be a key to replacing disk drives and flash memory in computing devices. Physicists at UC Davis and the Lawrence Berkeley National Laboratory are exploring how these patterns form in materials layered with graphene, an ultrathin form of carbon. A paper on the work was published online May 28 in Nature Materials.
By Becky Oskin
A simple method for manufacturing extremely low-density palladium nanofoams could help advance hydrogen storage technologies, reports a new study from the University of California, Davis.
UC Davis physicists Dustin Gilbert, Kai Liu and colleagues have come up with a new method to make a nanofoam of palladium. The foamy metal could be used to store hydrogen in vehicles or for other purposes. (Image credit: Dustin Gilbert and Kai Liu, UC Davis)
Full post: New Technique Makes Light Metallic Nanofoam
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By Becky Oskin
Solar cells made from perovskites have sparked great excitement in recent years because the crystalline compounds boast low production costs and high energy efficiencies. Now UC Davis scientists have found that some promising compounds — the hybrid lead halide perovskites — are chemically unstable and may be unsuited for solar cells.
“We have proven these materials are highly unlikely to function on your rooftop for years,” said Alexandra Navrotsky, interdisciplinary professor of ceramic, earth, and environmental materials chemistry at UC Davis and director of the Nanomaterials in the Environment, Agriculture, and Technology (NEAT) organized research unit.
Our electronic devices are based on what happens when different materials are layered together: “The interface is the device,” as Nobel laureate Herbert Kroemer famously claimed over 40 years ago. Right now, our microchips and memory devices are based on the movement of electrons across and near interfaces, usually of silicon, but with limitations of conventional electronics become apparent, researchers are looking at new ways to store or process information. These “heterostructures” can also find applications in advanced batteries and fuel cells.
Now physicists at UC Davis have observed what’s going on at some of these interfaces as oxygen ions react with different metals, causing drastic changes in magnetic and electronic properties.
UC Davis researchers have developed a way to use the empty shell of a Hepatitis E virus to carry vaccines or drugs into the body. The technique has been tested in rodents as a way to target breast cancer, and is available for commercial licensing through UC Davis Office of Research.
Hepatitis E virus is feco-orally transmitted, so it can survive passing through the digestive system, said Marie Stark, a graduate student working with Professor Holland Cheng in the UC Davis Department of Molecular and Cell Biology.
A new virus-killing peptide springs from an unexpected source: another virus, Hepatitis C.
Now biomedical engineers at UC Davis and Nanyang Technological University, Singapore show how the HCV alpha-helical (AH) peptide can make holes in the types of membranes that surround viruses. The work is published Jan. 5 in Biophysical Journal.
HCV-AH is known to be active against a wide range of viruses including West Nile, dengue, measles and HIV.
The HCV-AH peptide appears to target an Achilles’ heel common to many viruses, most likely a property of the lipid coating or envelope, said study author Atul Parikh, professor of biomedical engineering at UC Davis. That means that it’s less likely that viruses can readily evolve to become resistant to the peptide.
By Holly Ober
Thermal ablation with magnetic resonance–guided focused ultrasound surgery (MRgFUS) is a noninvasive technique for treating fibroids and cancer. New research from UC Davis shows that combining the technique with chemotherapy can allow complete destruction of tumors in mice.
MRgFUS combines an ultrasound beam that heats and destroys tissue with a magnetic resonance imaging to guide the beam and monitor the effects of treatment. The effectiveness of the treatment can be limited by the need to spare normal tissue or critical structures on the tumor margins, as well as the need to eliminate micrometastases.
An exotic, swirling object with the sci-fi name of a “magnetic skyrmion” could be the future of nanoelectronics and memory storage. Physicists at UC Davis and the National Institute of Standards and Technology (NIST) have now succeeded in making magnetic skyrmions, formerly found at temperatures close to absolute zero, at room temperature.
“This is a potentially new way to store information, and the energy costs are expected to be extremely low,” said Kai Liu, professor of physics at UC Davis and corresponding author of a paper on the work, published in the journal Nature Communications Oct. 8.