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Archive for the ‘materials’ category: Page 159

Nov 18, 2021

What Causes “Old Book Smell”?

Posted by in categories: chemistry, materials

“A combination of grassy notes with a tang of acids and a hint of vanilla over an underlying mustiness” is how an international team of chemists describes the unique odor of old books in a study. Poetic, sure, but what causes it?

Books are made up almost entirely of organic materials: paper, ink, glue, fibers. All these materials react to light, heat, moisture, and even each other over the years, and release a number of volatile organic compounds (VOCs). While the blend of compounds released by any one book is dependent on the exact things that went into making it, there’s only so much variation in materials.

The researchers tested 72 books and found some 15 compounds that came up again and again. They were reliable markers for degradation. These include acetic acid, benzaldehyde, butanol, furfural, octanal, methoxyphenyloxime, and other chemicals with funny-sounding names. A book’s smell is also influenced by its environment and materials it encounters over the course of its life (which is why some books have hints of cigarette smoke, others smell a little like coffee, and still others, cat dander).

Nov 16, 2021

Realization of active metamaterials with odd micropolar elasticity

Posted by in category: materials

Mechanical metamaterials can be engineered with properties not possible in ordinary materials. Here the authors demonstrate and study an active metamaterial with self-sensing characteristics that enables odd elastic properties not observed in passive media.

Nov 15, 2021

Effect of early treatment with fluvoxamine on risk of emergency care and hospitalisation among patients with COVID-19: the TOGETHER randomised, platform clinical trial

Posted by in categories: biotech/medical, materials

I may have already posted about this, but this is more data from The Lancet.

Background.

Recent evidence indicates a potential therapeutic role of fluvoxamine for COVID-19. In the TOGETHER trial for acutely symptomatic patients with COVID-19, we aimed to assess the efficacy of fluvoxamine versus placebo in preventing hospitalisation defined as either retention in a COVID-19 emergency setting or transfer to a tertiary hospital due to COVID-19.

Continue reading “Effect of early treatment with fluvoxamine on risk of emergency care and hospitalisation among patients with COVID-19: the TOGETHER randomised, platform clinical trial” »

Nov 13, 2021

Scientists detected spooky quantum entanglement in solid materials

Posted by in categories: materials, quantum physics

Scientists demonstrate how quantum entanglement can be witnessed in the quasi-1D Heisenberg antiferromagnet.

Nov 13, 2021

Ruby that hides 2.5 billion-year-old signs of life is one precious gem

Posted by in categories: biological, materials

If you own any piece of jewelry with a ruby, you’re probably never going to look at it the same way again.

Forget those perfect gemstones you see glittering in store displays. What scientists are looking for are the flawed ones — the ones that contain inclusions which can whisper the secrets of Earth’s distant past, like that tardigrade trapped in amber. When researcher Chris Yakymchuk and his team unearthed a peculiar ruby in Greenland, the inclusion they found was what remained of life that was over 2.5 billion years old.

What was inside the ruby sounds common enough. Graphite is the same material pencils write with, but it is also a pure form of carbon that Yakymchuk determined to be all that was left of prehistoric microbes, possibly the same cyanobacteria (blue-green algae) that first released oxygen into Earth’s atmosphere through photosynthesis. He led a study recently published in Ore Geology Reviews.

Nov 13, 2021

AI behind Deepfakes may Power Materials Design Innovations

Posted by in categories: materials, robotics/AI

The person staring back from the computer screen may not actually exist, thanks to artificial intelligence (AI) capable of generating convincing but ultimately fake images of human faces. Now this same technology may power the next wave of innovations in materials design, according to Penn State scientists.

“We hear a lot about deepfakes in the news today – AI that can generate realistic images of human faces that don’t correspond to real people,” said Wesley Reinhart, assistant professor of materials science and engineering and Institute for Computational and Data Sciences faculty co-hire, at Penn State. “That’s exactly the same technology we used in our research. We’re basically just swapping out this example of images of human faces for elemental compositions of high-performance alloys.”

The scientists trained a generative adversarial network (GAN) to create novel refractory high-entropy alloys, materials that can withstand ultra-high temperatures while maintaining their strength and that are used in technology from turbine blades to rockets.

Nov 11, 2021

Self-healing plastic repairs itself in 10 seconds even under water

Posted by in category: materials

A new type of plastic can rapidly heal itself under water, even in harsh conditions. It maintains its strength after self-healing, so it may be useful in emergencies at sea.

Lili Chen at Tsinghua University in China and her colleagues developed this material, called Rapid Underwater Self-healing Stiff Elastomer (RUSSE) because most self-healing polymers don’t work very well under water. “Room temperature self-healing polymers generally have a poor underwater stability, low healing strength and a slow healing process,” says Chen.

Continue reading “Self-healing plastic repairs itself in 10 seconds even under water” »

Nov 11, 2021

Using ocean plastic waste to power ocean cleanup ships

Posted by in categories: energy, materials

A team of researchers from Worcester Polytechnic Institute, Woods Hole Oceanographic Institution and Harvard University believes that the plastic amassing in floating islands in the oceans could be used to power the ships that are sent to clean them up. In their paper published in Proceedings of the National Academy of Sciences, the group describes how ocean plastics could be converted to ship fuel.

Prior research has shown that millions of tons of plastics enter the each year—some of it is ground into fragments and disperses, and some of it winds up in colossal garbage patches floating in remote parts of the ocean. Because of the danger that such plastics present to ocean life, some environmentalists have begun cleanup operations. Such operations typically involve sending a ship to a garbage patch, collecting as much as the ship will hold and then bringing it back to port for processing. In this new effort, the researchers suggest it would be far more efficient and greener to turn the into fuel for both a processing machine and for uninterrupted operation of the ships.

The researchers note that the plastic in a could be converted to a type of oil via hydrothermal liquefaction (HTL). In this process, the plastic is heated to 300–550 degrees Celsius at pressures 250 to 300 times that of sea-level conditions. The researchers have calculated that a ship carrying an HTL converter would be capable of producing enough oil to run the HTL converter and the ship’s engine. Under their scenario, plastic collection booms would be permanently stationed at multiple sites around a large patch, able to load the plastic it collects onto ships.

Nov 10, 2021

This long-lasting hydrogel could be used to replace damaged human tissues

Posted by in category: materials

More entanglements in the material help polymer chains slip without breaking.

Nov 6, 2021

Say goodbye to air conditioning with new roofing material

Posted by in category: materials

The guilt-free air conditioning, called “cooling paper,” is made from recyclable paper and doesn’t use any electricity.