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Tough, strong and heat-enduring: Bioinspired material to replace plastics – Phys.org

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Based on different commercially available raw materials (e.g., TiO2-mica, Fe2O3-mica), a variety of all-natural bioinspired structural materials with different colors can be fabricated. Credit: GUAN Qingfang

Modern life relies heavily on plastics, even though their petroleum-based production creates serious environmental challenges. Industry currently lacks sustainable alternatives due to their limited mechanical properties or complex manufacturing processes. An advanced strategy to design and produce high-performance sustainable structural materials is hence greatly needed.

Just such a new bioinspired material is now available to replace petroleum-based plastics. A team led by Prof. Shu-Hong Yu from the University of Science and Technology of China (USTC) reports a method to manufacture materials with similar as nacre from wood-derived fiber and mica, with adaption to mass production, good processability, and tunable coloration.

Natural nacre has a hierarchically ordered structure at multiscale levels, just like bricks and mortar, enabling it to be of both strength and toughness. Inspired by nacre, the researchers mimic the ordered brick-and-mortar structure using the TiO2 coated mica microplatelet (TiO2-mica) and cellulose nanofiber (CNF) by the proposed directional deforming assembly method.

This method directly presses the hydrogel of TiO2-mica and CNF, while keeps the size on in-plane directions unchanged. The thickness of the hydrogel is dramatically reduced and materials are directly constructed with the highly ordered brick-and-mortar structure.

At the nanoscale, the TiO2 nano-grains on the surface of TiO2-mica lead to efficient energy dissipation by frictional sliding during TiO2-mica pull-out. All the hierarchically ordered structure at multiscale levels contribute to the load redistribution and toughness enhancement.

  • Tough, strong and heat-endure: Bioinspired material to oust plastics
    A mobile phone case prototype made from this bioinspired material. Thanks to its good processability, the material can be fabricated into desired shape and size, showing a vast potential to replace plastics for practical applications, for example, structural support for high-end personal electronic device. Credit: GUAN Qingfang
  • Tough, strong and heat-endure: Bioinspired material to oust plastics
    Because the proposed manufacture method, directional deforming assembly, is effective and scalable, mass production of all-natural bioinspired structural material can be achieved. Credit: GUAN Qingfang

The obtained materials have excellent strength (~281 MPa) and toughness (~11.5 MPa m1/2), which are more than 2 times higher than those of high-performance engineering plastics (e.g., polyamides, aromatic polycarbonate), making it a strong competitor to petroleum-based plastics.

Even better, these materials adapt to temperature ranging from -130 °C to 250 °C, while normal plastics easily soften at high temperature. Therefore, such materials are safer and more reliable at high or variable temperatures.


Explore further

Sustainable biosynthetic transparent films developed for plastic substitute


More information:
Qing-Fang Guan et al, An all-natural bioinspired structural material for plastic replacement, Nature Communications (2020). DOI: 10.1038/s41467-020-19174-1

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University of Science and Technology of China

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Tough, strong and heat-enduring: Bioinspired material to replace plastics (2020, November 9)
retrieved 9 November 2020
from https://phys.org/news/2020-11-tough-strong-heat-enduring-bioinspired-material.html

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'The blob': Scientists confirm discovery of a completely new undersea species – Timmins Press

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Thanks to its love for extreme depths and remote oceanic corners, no one had ever seen the blob, or even knew it existed

Meet Duobrachium sparksae – a strange, gelatinous species of ctenophore, encountered during a dive off the coast of Puerto Rico.

NOAA fisheries

Deep in the dark, murky waters of our oceans, a gelatinous blob, shaped like a dislodged human molar, floats along the seabed.

Thanks to its love for extreme depths and remote oceanic corners, no one had ever seen the blob, or even knew it existed, until a team of scientists accidentally discovered it during a deep-sea dive off the coast of Puerto Rico in 2015, with help from an underwater, remotely-operated vehicle called ‘Deep Discover.’

Five years on, in a paper published this month, scientists with the National Oceanic and Atmospheric Administration (NOAA) have confirmed that the blob is an entirely new species of undersea creature, Duobrachium sparksae – a never-before-seen species of jelly-like ctenophore. It’s also the first time that researchers have discovered a species using high-definition video footage only.

“It’s unique because we were able to describe a new species based entirely on high-definition video,” explained NOAA marine biologist Allen Collins in a release.

“We don’t have the same microscopes as we would in a lab, but the video can give us enough information to understand the morphology in detail, such as the location of their reproductive parts and other aspects.”

Ctenophores, also known as comb jellies, have bulbous, balloon-like bodies, from which protrude two tentacle-like strings, known as cilia. There are between 100 and 150 species of comb jellies, according to the NOAA, and despite their name, they are not at all related to jellyfish. Ctenophores, the group explains, are carnivorous, and many are highly efficient predators that eat small arthropods and many kinds of larvae.

[embedded content]

Three different specimens were filmed by the vehicle at depths around 3,900 metres, in an underwater area called the Arecibo Amphitheater, which lies within a trench known as the Guajataca Canyon, off Puerto Rico. One of the animals appeared to use its tentacles to touch the seabed, scientists said. 

“It was a beautiful and unique organism,” oceanographer Mike Ford was quoted as saying in a release.

“It moved like a hot air balloon attached to the seafloor on two lines, maintaining a specific altitude above the seafloor. Whether it’s attached to the seabed, we’re not sure. We did not observe direct attachment during the dive, but it seems like the organism touches the seafloor.”

Identifying a new species solely via photographic and video evidence has often yielded contentious results, the scientists explained in their paper, as natural classification “relies heavily” on the physical specimen samples preserved in museums “to serve as references to which other material can be compared.”

“Indeed, the idea of using photographic evidence to establish new species has been highly contentious in recent decades.”

In this case, however, the team was able to avoid any pushback due to the high-definition quality of the footage they recorded of the three observed specimens. The team hopes to collect real-life specimens on future dives, but fears it may be decades before they run into the species again.

“Even if we had the equipment, there would have been very little time to process the animal because gelatinous animals don’t preserve very well,” Collins said.

“Ctenophores are even worse than jellyfish in this regard.”

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After Arecibo, NASA isn't sure what comes next for planetary radar – Space.com

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Arecibo Observatory’s massive radio telescope has collapsed; with it has gone a crucial tool in understanding asteroid risks to Earth — and it would take a serious government initiative to replace.

Before the facility sustained irreversible damage in a series of cable failures this year, Arecibo Observatory was Earth’s most powerful planetary radar system. Astronomers can’t use radar to discover new asteroids, but the data that these systems provide can give scientists the details about an object’s size, shape and location they need to better and more quickly evaluate the threat that individual asteroids might pose to Earth. 

“This is a hard thing to have to take [down] an iconic facility like this that’s provided so much for the radio astronomy and planetary radar community over so many decades; it’s really sad to see,” Lindley Johnson, who leads NASA’s Planetary Defense Coordination Office, said during a virtual meeting of NASA’s Planetary Advisory Committee held on Nov. 30, the day before the structure collapsed. “It’s certainly not an ideal situation, but I think it really comes down to, it’s time to really get moving on investing in a new planetary radar capability.”

Related: Losing Arecibo’s giant dish leaves humans more vulnerable to space rocks, scientists say

But that’s easier said than done. There are two key complications at play when it comes to investing in planetary radar capability.

One is bureaucratic: Planetary radar has to be done from Earth’s surface. And while NASA leads the country’s asteroid-focused work, the U.S. National Science Foundation (NSF) heads the federal government’s ground-based observations, as it does Arecibo Observatory; NASA merely paid for observation time on the radar system. With the sole exception of NASA’s Infrared Telescope Facility in Hawaii, all of the agency’s observing facilities are in space.

(This is also complicated. Technically, the world’s other planetary radar facility, at Goldstone in California, is run by NASA, but that’s because its primary duty is to communicate with spacecraft traversing the solar system. The radar facility recently completed an upgrade and is back to normal observations, although it has a less flexible schedule than Arecibo did and can’t see objects as far from Earth.)

Related: Losing Arecibo Observatory would create a hole that can’t be filled, scientists say 

“The way our agencies are tasked, ground-based observations are the responsibility of NSF,” Lori Glaze, who leads NASA’s Planetary Science Division, said during the same meeting. “It’s not in NASA’s purview.”

A second complication is the cost. A radar beam as powerful as Arecibo’s requires both a powerful transmitter and a massive radio dish, neither of which is cheap. 

Taken together, the challenges mean that NASA would likely need to work out agreements with one or more government counterparts before a new planetary radar system comes online.

“This kind of thing really takes a partnership of agencies,” Johnson said, adding that Arecibo itself traced its roots to a Department of Defense-led partnership. Something similar could rev up planetary radar, he said. “We do definitely have an opportunity and an interest in partnering with the U.S. Space Force on a more capable radar system.” The military branch is interested in the technology as a way to track satellites between Earth and the moon, he added.

Related: Arecibo isn’t the first radio telescope to unexpectedly fail. Here’s what we can learn from Green Bank’s collapse.

A reduction in planetary radar doesn’t strike at the heart of NASA’s planetary defense system, which focuses on discovering and tracking relatively large asteroids that come relatively close to Earth. Spotting such objects relies on facilities that detect optical and infrared light and scan large swaths of the sky regularly enough to notice when a new, fast-moving dot appears against the background of stars.

Radar can’t do that; it requires that scientists have a good idea of precisely where the object they want to study is, so that they can point the narrow radar beam precisely enough to bounce off the object. Instead, planetary defense experts use radar to more quickly plot an object’s orbit farther into the future and to determine characteristics of the object like its shape and density that might affect attempts to deflect an asteroid if it does appear to be on course to impact Earth.

“As far as planetary defense and NEO [near-Earth object] observations are concerned, it’s only a slight negative impact,” Johnson said of the loss of Arecibo’s radar system. “It doesn’t affect our discovery rate of near-Earth objects at all, it only has some impact on the opportunities we have to characterize these objects.”

Radar data of an asteroid dubbed Phaethon captured by Arecibo Observatory in December 2017. (Image credit: Arecibo Observatory/NASA/NSF)

Nevertheless, radar data is nice to have — and definitely the sort of thing Johnson would want for the planetary defense community.

Green Bank Observatory in West Virginia was already planning to add radar capability to its primary radio dish before the loss of Arecibo, scientists say, although the system, like that at Goldstone, won’t replicate Arecibo’s specific skills. And even that new capability would build on an existing facility, rather than starting from scratch, which comes with both benefits and risks.

“In a perfect world, I would pursue a new planetary radar capability,” Johnson said, even before Arecibo’s final collapse. “Trying to keep these old facilities going — they are high maintenance.”

But new capability wouldn’t mean a copy of Arecibo’s iconic dish, he emphasized. “It’s really time to be looking at the next generation of planetary radar capabilities,” he said, in particular hypothesizing that an array of dishes may be a more appealing approach now than Arecibo’s single massive dish.

“Technology has moved on since the 30, 40 years ago that the radar capability was installed at Arecibo,” Johnson said. “We need to take advantage.”

Email Meghan Bartels at mbartels@space.com or follow her on Twitter @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook. 

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'The blob': Scientists confirm discovery of a completely new undersea species – Alberta Daily Herald Tribune

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Thanks to its love for extreme depths and remote oceanic corners, no one had ever seen the blob, or even knew it existed

Meet Duobrachium sparksae – a strange, gelatinous species of ctenophore, encountered during a dive off the coast of Puerto Rico.

NOAA fisheries

Deep in the dark, murky waters of our oceans, a gelatinous blob, shaped like a dislodged human molar, floats along the seabed.

Thanks to its love for extreme depths and remote oceanic corners, no one had ever seen the blob, or even knew it existed, until a team of scientists accidentally discovered it during a deep-sea dive off the coast of Puerto Rico in 2015, with help from an underwater, remotely-operated vehicle called ‘Deep Discover.’

Five years on, in a paper published this month, scientists with the National Oceanic and Atmospheric Administration (NOAA) have confirmed that the blob is an entirely new species of undersea creature, Duobrachium sparksae – a never-before-seen species of jelly-like ctenophore. It’s also the first time that researchers have discovered a species using high-definition video footage only.

“It’s unique because we were able to describe a new species based entirely on high-definition video,” explained NOAA marine biologist Allen Collins in a release.

“We don’t have the same microscopes as we would in a lab, but the video can give us enough information to understand the morphology in detail, such as the location of their reproductive parts and other aspects.”

Ctenophores, also known as comb jellies, have bulbous, balloon-like bodies, from which protrude two tentacle-like strings, known as cilia. There are between 100 and 150 species of comb jellies, according to the NOAA, and despite their name, they are not at all related to jellyfish. Ctenophores, the group explains, are carnivorous, and many are highly efficient predators that eat small arthropods and many kinds of larvae.

[embedded content]

Three different specimens were filmed by the vehicle at depths around 3,900 metres, in an underwater area called the Arecibo Amphitheater, which lies within a trench known as the Guajataca Canyon, off Puerto Rico. One of the animals appeared to use its tentacles to touch the seabed, scientists said. 

“It was a beautiful and unique organism,” oceanographer Mike Ford was quoted as saying in a release.

“It moved like a hot air balloon attached to the seafloor on two lines, maintaining a specific altitude above the seafloor. Whether it’s attached to the seabed, we’re not sure. We did not observe direct attachment during the dive, but it seems like the organism touches the seafloor.”

Identifying a new species solely via photographic and video evidence has often yielded contentious results, the scientists explained in their paper, as natural classification “relies heavily” on the physical specimen samples preserved in museums “to serve as references to which other material can be compared.”

“Indeed, the idea of using photographic evidence to establish new species has been highly contentious in recent decades.”

In this case, however, the team was able to avoid any pushback due to the high-definition quality of the footage they recorded of the three observed specimens. The team hopes to collect real-life specimens on future dives, but fears it may be decades before they run into the species again.

“Even if we had the equipment, there would have been very little time to process the animal because gelatinous animals don’t preserve very well,” Collins said.

“Ctenophores are even worse than jellyfish in this regard.”

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