Lifeboat Foundation

A team of chemists from MIT and Duke University has discovered a counterintuitive way to make polymers stronger: introduce a few weaker bonds into the material.

Working with a type of polymer known as polyacrylate elastomers, the researchers found that they could increase the materials’ resistance to tearing up to tenfold, simply by using a weaker type of crosslinker to join some of the polymer building blocks.

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MIT engineers have synthesized a superabsorbent material that can soak up a record amount of moisture from the air, even in desert-like conditions.

As the material absorbs water vapor, it can swell to make room for more moisture. Even in very dry conditions, with 30 percent relative humidity, the material can pull vapor from the air and hold in the moisture without leaking. The water could then be heated and condensed, then collected as ultrapure water.

The transparent, rubbery material is made from hydrogel, a naturally absorbent material that is also used in disposable diapers. The team enhanced the hydrogel’s absorbency by infusing it with lithium chloride — a type of salt that is known to be a powerful dessicant.

MIT researchers have found a new mechanism by which the superconductor iron selenide transitions into a superconducting state. Unlike other iron-based superconductors, iron selenide’s transition involves a collective shift in atoms’ orbital energy, not atomic spins. This breakthrough opens up new possibilities for discovering unconventional superconductors.

Under certain conditions — usually exceedingly cold ones — some materials shift their structure to unlock new, superconducting behavior. This structural shift is known as a “nematic transition,” and physicists suspect that it offers a new way to drive materials into a superconducting state where electrons can flow entirely friction-free.

But what exactly drives this transition in the first place? The answer could help scientists improve existing superconductors and discover new ones.

Using data from the Spitzer space observatory, Dr. Susana Iglesias-Groth, a researcher from The Instituto de Astrofísica de Canarias (IAC), has found evidence for the existence of the amino acid tryptophan in the interstellar material in a nearby star-forming region. The research is published in Monthly Notices of the Royal Astronomical Society.

High amounts of tryptophan were detected in the Perseus molecular complex, specifically in the IC348 star system, a star-forming region that lies 1,000 light years away from Earth—relatively close in astronomical terms. The region is generally invisible to the naked eye, but shines brightly when viewed in infrared wavelengths.

Tryptophan is one of the 20 amino acids essential for the formation of key proteins for life on Earth, and produces one of the richest pattern of spectral lines in the infrared. It was therefore an obvious candidate to be explored using the extensive spectroscopic database of the Spitzer satellite, a space-based infrared telescope.

Architecture studio Snøhetta has released photos showing how its underwater restaurant, Under, has become covered in marine life since reaching completion in Norway three years ago.

Located in the remote Lindesnes area, the 495-square-metre structure is submerged off of a craggy shoreline and now doubles as an artificial reef.

The Norwegian studio designed Under as a concrete tube that is intended to resemble a sunken periscope. The concrete was left exposed externally, forming a rough finish onto which algae and molluscs can latch.

Under certain conditions—usually exceedingly cold ones—some materials shift their structure to unlock new, superconducting behavior. This structural shift is known as a “nematic transition,” and physicists suspect that it offers a new way to drive materials into a superconducting state where electrons can flow entirely friction-free.

But what exactly drives this transition in the first place? The answer could help scientists improve existing superconductors and discover new ones.

Now, MIT physicists have identified the key to how one class of superconductors undergoes a nematic transition, and it’s in surprising contrast to what many scientists had assumed.

Cultured meat starts with the extraction of cells from an animal’s tissue, be it a pig, cow, chicken, fish, or any other animal we consume. The cell extraction doesn’t kill or even harm the animal. The cells are mixed with a cocktail of nutrients, oxygen, and moisture inside large bioreactors. Mimicking the environment inside an animal’s body, the bioreactors are kept at a warm temperature, and the cells inside divide, multiply, and mature. Waste products are regularly removed to keep the environment pure.

Once the cells have reached maturity—that is, grown into small chunks of muscle-like material—they’re harvested from the bioreactors to be refined and shaped into a final product. This can involve anything from extrusion cooking and molding to 3D printing and adding in artificial fat.

JBS says the factory it’s building in Spain will be able to produce more than 1,000 metric tons of cultivated beef per year, and could expand capacity to 4,000 metric tons per year in the medium term. That’s smaller than Believer Meats’ facility in the US, which will have an annual production capacity of 10,000 metric tons. But what’s noteworthy about the JBS factory is that it’s focused on producing beef.

The field of photonics has seen significant advances during the past decades, to the point where it is now an integral part of high-speed, international communications. For general processing photonics is currently less common, but is the subject of significant research. Unlike most photonic circuits which are formed using patterns etched into semiconductor mask using lithography, purely light-based circuits are a tantalizing possibility. This is the focus of a recent paper (press release, ResearchGate) in Nature Photonics by [Tianwei Wu] and colleagues at the University of Pennsylvania.

What is somewhat puzzling is that despite the lofty claims of this being ‘the first time’ that such an FPGA-like device has been created for photonics, this is far from the case, as evidenced by e.g. a 2017 paper by [Kaichen Dong] and colleagues (full article PDF) in Advanced Materials. Here the researchers used a slab of vanadium dioxide (VO₂) with a laser to heat sections to above 68 °C where the material transitions from an insulating to a metallic phase and remains that way until the temperature is lowered again. The μm-sized features that can be created in this manner allow for a wide range of photonic devices to be created.

What does appear to be different with the photonic system presented by [Wu] et al. is that it uses a more traditional 2D approach, with a slab of InGaAsP on which the laser pattern is projected. Whether it is more versatile than other approaches remains to be seen, with the use of fully photonic processors in our computers still a long while off, never mind photonics-accelerated machine learning applications.

A new high-performance metal alloy, called a superalloy, could help boost the efficiency of the turbines used in power plants and the aerospace and automotive industries.

Created using a 3D printer, the superalloy is composed of a blend of six elements that altogether form a material that’s both lighter and stronger than the standard materials used in conventional turbine machinery. The strong superalloy could help industries cut both costs and carbon emissions — if the approach can be successfully scaled up.

The challenge: In the world of materials science, the search for new metal alloys has been heating up in recent years. For over a century, we’ve depended on relatively simple alloys like steel, composed of 98% iron, to form the backbone of our manufacturing and construction industries. But today’s challenges demand more: alloys that can withstand higher temperatures and remain strong under stress, yet still be lightweight.