In recent years, researchers at The University of Texas at Dallas and colleagues at the University of Wollongong in Australia have put a high-tech twist on the ancient art of fiber spinning, using modern materials to create ultra-strong, powerful, shape-shifting yarns.
In a perspective article published Sept. 26 online in the Proceedings of the National Academy of Sciences, a team of scientists at UT Dallas’ Alan G. MacDiarmid NanoTech Institute describes the path to developing a new class of artificial muscles made from highly twisted fibers of various materials, ranging from exotic carbon nanotubes to ordinary nylon thread and polymer fishing line.
Because the artificial muscles can be made in different sizes and configurations, potential applications range from robotics and prosthetics to consumer products such as smart textiles that change porosity and shape in response to temperature.
“We call these actuating fibers ‘artificial muscles’... more
Glow-in-the-dark stickers, weird deep-sea fish, LED lightbulbs — all have forms of luminescence. In other words, instead of just reflecting light, they make their own.
Now a team of scientists from the University of Vermont and Dartmouth College have discovered a new way that some molecules can make a luminescent glow — a strange, bright green.
“It’s a new method to create light,” says Matthew Liptak, a chemist at UVM who co-led the new research. The new light may have many promising applications including novel kinds of LED bulbs and medical dyes “that can sense viscosity within a cell,” he says. The discovery was reported Sept. 26 in the journal Nature Chemistry.
To understand how this new light is formed, consider maple syrup. It’s a thick liquid. The scientists at Dartmouth, led by chemist Ivan Aprahamian, were exploring... more
Every material can bend and break. Through nearly a century’s worth of research, scientists have had a pretty good understanding of how and why.
But, according to new findings from Drexel University materials science and engineering researchers, our understanding of how layered materials succumb to stresses and strains was lacking. The report suggests that, when compressed, layered materials — everything from sedimentary rocks, to beyond-whisker-thin graphite — will form a series of internal buckles, or ripples, as they deform.
The finding was published in the journal Scientific Reports by a team of researchers from Drexel’s College of Engineering, led by Michel W. Barsoum, PhD, distinguished professor and head of the MAX/MXene Research Group, along with Garritt J. Tucker, PhD, an assistant professor, and Mitra Taheri, PhD... more
New analysis finds way to safely conduct heat from graphene to biological tissues.
In the future, our health may be monitored and maintained by tiny sensors and drug dispensers, deployed within the body and made from graphene — one of the strongest, lightest materials in the world. Graphene is composed of a single sheet of carbon atoms, linked together like razor-thin chicken wire, and its properties may be tuned in countless ways, making it a versatile material for tiny, next-generation implants.
But graphene is incredibly stiff, whereas biological tissue is soft. Because of this, any power applied to operate a graphene implant could precipitously heat up and fry surrounding cells.
Now, engineers from MIT and Tsinghua University in Beijing have precisely simulated... more
Coffee is one of the most popular drinks in the U.S., which makes for a perky population — but it also creates a lot of used grounds. Scientists now report in the journal ACS Sustainable Chemistry & Engineering an innovative way to reduce this waste and help address another environmental problem. They have incorporated spent coffee grounds in a foam filter that can remove harmful lead and mercury from water.
Restaurants, the beverage industry and people in their homes produce millions of tons of used coffee grounds every year worldwide, according to researcher Despina Fragouli. While much of the used grounds go to landfills, some of them are applied as fertilizer, used as a biodiesel... more
Berkeley Lab scientists use fluorescence to boost the performance of cool colored pigments
Elementary school science teaches us that in the sun, dark colors get hot while white stays cool. Now new research from Lawrence Berkeley National Laboratory (Berkeley Lab) has found an exception: Scientists have determined that certain dark pigments can stay just as cool as white by using fluorescence, the re-emission of absorbed light.
The researchers tested this concept by coloring cool roof coatings with ruby red (aluminum oxide doped with chromium). Led by Berkeley Lab scientist Paul Berdahl, they first found that white paint overlaid with a layer of ruby crystals stayed as cool as a commercial white coating. Next, they synthesized ruby pigment to mix into coatings. Their results were... more
James Clarkson, Alan Farhan, and Andreas Scholl/Berkeley Lab
New multiferroic material by Berkeley Lab and Cornell researchers is a big step in march toward ultra-low power electronics
Scientists have successfully paired ferroelectric and ferrimagnetic materials so that their alignment can be controlled with a small electric field at near room temperatures, an achievement that could open doors to ultra low-power microprocessors, storage devices and next-generation electronics.
The work, co-led by researchers at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and Cornell University, is described in a study to be published Sept. 22 in the journal Nature.
The researchers engineered thin, atomically precise films of hexagonal lutetium iron oxide (LuFeO3), a material known to be a robust ferroelectric, but not strongly magnetic. Lutetium... more
What if it were possible to quickly and inexpensively manufacture a part simply by using a series of close-range digital images taken of the object?
Michael Immel, instructor in the Harold and Inge Marcus Department of Industrial and Manufacturing Engineering, originally started thinking about the technique, called photogrammetry, for a different purpose, but quickly realized its application in manufacturing.
In this technique, digital images of an object that have been taken at various angles are used to create a point cloud — or a large collection of points used to create 3D representation of existing structures — from which a computer-aided design (CAD) file can be generated.
The resulting CAD file and subsequent 3D model could then be used to rebuild the part, or 3D print it, to its original specifications without using... more
Courtesy of the Materials Virtual Lab at UC San Diego
Nanoengineers at the University of California San Diego, in collaboration with the Materials Project at Lawrence Berkeley National Laboratory (Berkeley Lab), have created the world’s largest database of elemental crystal surfaces and shapes to date.
Dubbed Crystalium, this new open-source database can help researchers design new materials for technologies in which surfaces and interfaces play an important role, such as fuel cells, catalytic converters in cars, computer microchips, nanomaterials and solid-state batteries.
“This work is an important starting point for studying the material surfaces and interfaces, where many novel properties can be found. We’ve developed a new resource that can be used to better understand surface science and find better materials for surface-driven technologies,” said Shyue Ping Ong, a nanoengineering professor at UC San Diego and senior author of the study.
For example, fuel cell performance... more
A team of chemists has developed a method to yield highly detailed, three-dimensional images of the insides of batteries. The technique, based on magnetic resonance imaging, offers an enhanced approach to monitor the condition of these power sources in real time.
“One particular challenge we wanted to solve was to make the measurements 3D and sufficiently fast, so that they could be done during the battery-charging cycle,” explains NYU Chemistry Professor Alexej Jerschow, the paper’s senior author. “This was made possible by using intrinsic amplification processes, which allow one to measure small features within the cell to diagnose common battery failure mechanisms. We believe these methods could become important techniques for the development of better batteries.”
The work, described in Proceedings of the National Academy of Sciences, focuses on rechargeable Lithium-ion (Li-ion) batteries, which are used in cell phones, electric cars... more