It’s nearly 50 years since Gordon Moore predicted that the density of transistors on an integrated circuit would double every two years. “Moore’s Law” has turned out to be a self-fulfilling prophecy that technologists pushed to meet, but to continue into the future, engineers will have to make radical changes to the structure or composition of circuits. One potential way to achieve this is to develop devices based on single-molecule connections.
Nature has many examples of self-assembly, and bioengineers are interested in copying or manipulating these systems to create useful new materials or devices. Amyloid proteins, for example, can self-assemble into the tangled plaques associated with Alzheimer’s disease — but similar proteins can also form very useful materials, such as spider silk, or biofilms around living cells. Researchers at UC Davis and Rice University have now come up with methods to manipulate natural proteins so that they self-assemble into amyloid fibrils. The paper is published online by the journal ACS Nano.
Surfaces are very interesting to material scientists. The reactions that happen at the point where inside and outside meet, and elements interact with other chemicals or radiation, are important for developing new technology for batteries, fuel cells or photovoltaic panels, for catalysts for the chemical industry, and for understanding environmental chemistry and pollution. Now researchers at UC Davis and the Advanced Light Source at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory have combined two existing methods techniques to come up with a new method for studying surfaces with X-rays. This new technique is called SWAPPS, for Standing Wave Ambient Pressure Photoelectron Spectroscopy.
Contributed by AJ Cheline
Since 1963, UC Davis and Lawrence Livermore National Laboratory (LLNL) scientists and engineers have conducted joint interdisciplinary research that leverage the strengths of both institutions to address a variety of critical societal problems. Over the last year, leaders from LLNL and UC Davis have been working together to develop mechanisms that reinvigorate and deepen the partnerships between the institutions. Several joint faculty and lab researcher workshops have taken place over the last few months to identify and develop new topical areas of common interests. A number of joint grant proposals to federal funding agencies have been submitted and work is ongoing to identify funding mechanisms that facilitate additional collaborations.
A UC Davis engineering professor has received a grant of $200,000 from the National Science Foundation “Partnerships for Innovation: Accelerating Innovation Research- Technology Translation” program to move his silicon-based blades towards commercial development as surgical and shaving tools.
Silicon or ceramic blades are extremely sharp and hard, keeping an edge longer than metal blades, but they are expensive to manufacture. The technique recently invented by Saif Islam, professor of electrical and computer engineering at UC Davis, allows thin silicon blades to be mass-produced at much lower cost.
Glass has many applications that call for different properties, such as resistance to thermal shock or to chemically harsh environments. Glassmakers commonly use additives such as boron oxide to tweak these properties by changing the atomic structure of glass. Now researchers at the University of California, Davis, have for the first time captured atoms in borosilicate glass flipping from one structure to another as it is placed under high pressure.
The findings may have implications for understanding how glasses and similar “amorphous” materials respond at the atomic scale under stress, said Sabyasachi Sen, professor of materials science at UC Davis. Sen is senior author on a paper describing the work published Aug. 29 in the journal Science.
Silicon nanoparticles embedded in a zinc sulfide matrix are a promising material for new types of solar cell. Computational modeling by Stefan Wipperman, Gergely Zimanyi, Francois Gygi and Giulia Galli at UC Davis and colleagues shows how such a material might work.
“Designing materials with desired properties for renewable energy application is a topic of great current interest in physics, chemistry, and materials science, and one of the goals of the Materials Genome initiative, launched in the US in 2011. Our paper focuses on the search for design rules to predict Earth abundant materials for the efficient conversion of solar energy into electricity,” Zimanyi said in an email.
Researchers at UC Davis will soon have a new and very special tool to examine the structure and composition of materials at an atomic scale. The new Focused Ion Beam microscope, or dual-beam FIB, now being installed in the College of Engineering’s Center for Nano-Micromanufacturing (NCM2) is one of the first three instruments of its advanced type in the world — and currently the only one of its kind in the U.S..
“It will be transformative for materials science here,” said Klaus van Benthem, associate professor in the Department of Chemical Engineering and Materials Science. “We’ve never had images of this brilliance before.”
Recent work on a superconducting material first discovered at UC Davis is helping reveal the behavior of “unconventional” superconductors, and that physical pressure has a different type of effect on these materials than chemical doping.
The material, cerium cobalt indium-5 or CeCoIn5, belongs to the class of “unconventional” superconductors, said Nicholas Curro, a physics professor at UC Davis and coauthor on the work. CeCoIn5 was initially discovered in the laboratory of Professor Zachary Fisk when he was a faculty member at UC Davis; Fisk is now at UC Irvine.
Is there a different way to think about heat transfer? For about 150 years, scientists and engineers have used the concept of entropy to understand transfer of heat into mechanical work or between materials systems. Now a UC Davis professor and colleagues in China are putting forward an alternative, at least for some applications.
“To me, entropy is just a tool,” said Ning Pan, a materials scientist and professor of textiles and clothing, and biological engineering at UC Davis. “It does not work well in all cases, for example in understanding heating and cooling of materials.”