The shells of some mollusk species have compact helical structures that researchers propose develop from the self-assembly of a liquid-crystalline material.
New structures maintain the properties of high-pressure materials outside the high-pressure vessels in which they were formed.
Matthew Modoono/Northeastern University.
The innovative materials, known as thermoformable ceramics, were created by “accident” in a lab but had potential applications, including more effective and long-lasting heat sinks.
Materials known as metal-organic frameworks hold promise for advances in healthcare, energy and other areas, researchers say.
Inspired by living things, the unique material is 10 times as durable as natural rubber.
For the first time, researchers use only light and a catalyst to change properties such as hardness and elasticity in molecules of the same type, according to a new study published October 13 in Science.
The ability to control the physical properties of a material using light as a trigger is potentially transformative.
Textile engineers have developed a fabric woven out of ultra-fine nano-threads made in part of phase-change materials and other advanced substances that combine to produce a fabric that can respond to changing temperatures to heat up and cool down its wearer depending on need.
Materials scientists have designed an advanced textile with nano-scale threads containing in their core a phase-change material that can store and release large amounts of heat when the material changes phase from liquid to solid. Combining the threads with electrothermal and photothermal coatings that enhance the effect, they have in essence developed a fabric that can both quickly cool the wearer down and warm them up as conditions change.
A paper describing the manufacturing technique appeared in ACS Nano on August 10.
Researchers have developed an automatic drawing machine that uses pens and pencils to draw metamaterials onto paper. They demonstrated the new approach by using it to make three metamaterials that can be used to manipulate the microwave region of the electromagnetic spectrum.
Metamaterials are artificially engineered composite materials that derive their properties from patterned microstructures, rather than the chemical composition of the materials themselves. The exact shape, geometry, size, orientation and arrangement of the structures can be used to manipulate electromagnetic waves in ways that aren’t possible with conventional materials.
“Metamaterials, especially those used as absorbers, generally need to be thin, lightweight, wide and strong, but it isn’t easy to create thin and lightweight devices using traditional substrates,” said research team leader Junming Zhao from Nanjing University in China. “Using paper as the substrate can help meet these requirements while also lending itself to metasurfaces that conform to a surface or that are mechanically reconfigurable.”
CarbiCrete.
A key ingredient in concrete has always been cement, the production of which accounts for around 8 percent of the world’s greenhouse gas (GHG) emissions. While it may be tempting to think we are living in the age of plastic—after all, we have generated around 8 billion tonnes of plastic over the past 60 years and it turns out that the cement sector produces more than 30 billion tonnes of concrete each year.
Osaka Metropolitan University scientists have successfully developed a new positive electrode material Na2FeS2, consisting of sodium, iron, and sulfur. During testing, batteries using the Na2FeS2 positive electrode had a high energy storage capacity and could be charged and discharged for more than 300 cycles. Because the Na2FeS2 is made of abundant inexpensive elements, it is expected to be used in all-solid-state sodium batteries with higher capacity and lower costs.
The demand for high energy density rechargeable batteries, such as lithium-ion batteries, increases every year, as society shifts toward becoming carbon neutral. Sodium-ion batteries—which have a resource advantage over lithium-ion batteries —are attracting more attention, as cheap new high-performance materials continue to be developed.
A research group led by Associate Professor Atsushi Sakuda, President Masahiro Tatsumisago, and Professor Akitoshi Hayashi, at the Graduate School of Engineering, Osaka Metropolitan University, has successfully developed a new positive electrode, made of Na2FeS2, for all-solid-state sodium batteries. The batteries have a high energy storage capacity, high reversibility and use inexpensive elements that are readily available.
In the southern sky shine two smudges, known as the Large and Small Magellanic Clouds. They are satellite galaxies of the much larger Milky Way, and one of their qualities has puzzled scientists. As the Clouds tumble through space, the Milky Way should be exerting enough gravitational force to knock loose their star-making material. But the smaller galaxies are still building new stars. A study published Wednesday in the journal Nature finally explains it.
What they did — “A lot of people were struggling to explain how these streams of material could be there,” Dhanesh Krishnarao, assistant professor at Colorado College and lead author of the new study, says in a NASA description of the paper. “If this gas was removed from these galaxies, how are they still forming stars?”
