Lifeboat Foundation

Perovskite nanocrystals hold promise for improving a wide variety of optoelectronic devices—from lasers to light emitting diodes (LEDs) — but problems with their durability still limit the material’s broad commercial use.

Researchers at the Georgia Institute of Technology have demonstrated a novel approach aimed at addressing the material’s durability problem: encasing the perovskite inside a double-layer protection system made from plastic and silica.

In a study published Nov. 29 in the journal Science Advances, the research team describes a multistep process to produce encased perovskite nanocrystals that exhibit strong resistance to degradation in moist environments.

Researchers have identified a metal that conducts electricity without conducting heat — an incredibly useful property that defies our current understanding of how conductors work.

The metal, found in 2017, contradicts something called the Wiedemann-Franz Law, which basically states that good conductors of electricity will also be proportionally good conductors of heat, which is why things like motors and appliances get so hot when you use them regularly.

But a team in the US showed this isn’t the case for metallic vanadium dioxide (VO₂) — a material that’s already well known for its strange ability to switch from a see-through insulator to a conductive metal at the temperature of 67 degrees Celsius (152 degrees Fahrenheit).

The view from the HazeCam, which is situated just west of the Jackson Street Bridge in Newark, New Jersey, usually extends for about eight miles. To the east, the skyline of New York City rises and falls along the horizon like a bar graph, buffered by a blue haze of humidity and particulate emissions and ozone. The towers are planted into the rock of Manhattan, and the island of steel-and-concrete canyons covers 59 square kilometers and accommodates 1.5 million people. Techni…

The indoor biome covers as much as six percent of the world’s landmass—and we know almost nothing about it.

O, o.

In the world of materials science, many have heard of crystals—highly ordered structures in which atoms are arranged in a tight and periodic manner (in which the atomic arrangement is repeated). But, not many people know about quasicrystals, which are unique structures with strange atomic arrangements. Like crystals, quasicrystals are also tightly arranged, but what’s different about them is the fact that they possess an unprecedented pentagonal symmetry, such that the atomic arrangement is highly ordered but not periodic.

This distinctive feature gives them unique properties, like high stability, resistance to heat, and low friction. Since their discovery only about 30 years ago, scientists globally have been trying to understand the properties of quasicrystals, in an effort to make more advancements in materials research. But, this is not easy, as quasicrystals are not prevalent in nature. Luckily, they have been able to make use of structures similar to quasicrystals, called “Tsai-type approximants.” Understanding these structures in detail could give insights into the many properties of quasicrystals. One such property is antiferromagnetism, in which magnetic moments are aligned in a quasiperiodic order, strikingly distinguished from conventional antiferromagnets. This property has never been observed in quasicrystals so far, but the possibility was exciting for materials scientists, as it could be a gateway to a plethora of new applications.

Continue reading “New study shows unique magnetic transitions in quasicrystal-like structures” »

Supermassive black holes are true monsters of the Universe. From millions to even billions of times the mass of the Sun, there’s one in the very center of every big galaxy in the cosmos, and in fact each galaxy itself formed and grew along with its black hole; they affect each other profoundly. As matter falls onto the black hole it falls into an accretion disk, heats up, and emits huge amounts of energy and can also blow a fierce wind of material back into the galaxy (we call such galaxies with actively feeding supermassive black holes active galaxies). This wind can push away gas and dust that would otherwise fall onto the black hole, regulating its growth.

Under some conditions this wind can also compress the gas in the galaxy, which can increase the number of stars forming in the galaxy. But too much wind and the gas is blown right out of the galaxy. Even at some levels in between, it can heat the gas up enough that star formation is much harder. It’s like a pressure valve in the galaxy.

This is how it usually works, at least. Astronomers have found a compact group of galaxies clustered around an active galaxy, and that central galaxy’s black hole is so powerful it’s blowing a wind that’s causing star formation in the galaxies around it!

Physics experiment with ultrafast laser pulses produces a previously unseen phase of matter.

Cornell researchers have made a new discovery about how seemingly minor aspects of the internal structure of bone can be strengthened to withstand repeated wear and tear, a finding that could help treat patients suffering from osteoporosis. It could also lead to the creation of more durable, lightweight materials for the aerospace industry.

The team’s paper, “Bone-Inspired Microarchitectures Achieve Enhanced Fatigue Life,” was published Nov. 18 in the Proceedings of the National Academy of Sciences. Co-authors include Cornell doctoral students Cameron Aubin and Marysol Luna; postdoctoral researcher Floor Lambers; Pablo Zavattieri and Adwait Trikanad at Purdue University; and Clare Rimnac at Case Western Reserve University.

Continue reading “Bone breakthrough may lead to more durable airplane wings” »

Regrowing bones is no easy task, but the world’s lightest solid might make it easier to achieve. Researchers have figured out a way to use hybrid aerogels, strong but ultralight materials, to prompt new bone tissue to grow and replace lost or damaged tissue.

Although bone cancer is a relatively rare disease (it accounts for less than 1% of all cancers), people who suffer from it often end up losing a lot of bone tissue and, in extreme cases, undergo amputation. The cancerous tissue has to be cut out, taking with it a large chunk of nearby healthy tissue to make sure that the cancer does not spread. This effectively removes the cancer, but also leaves the patient with a lot less bone than they started out with.

Continue reading “Say goodbye to casts: ‘magic’ material can heal your bones in mere days” »

Scientists have long theorized that the energy stored in the atomic bonds of nitrogen could one day be a source of clean energy. But coaxing the nitrogen atoms into linking up has been a daunting task. Researchers at Drexel University’s C&J Nyheim Plasma Institute have finally proven that it’s experimentally possible—with some encouragement from a liquid plasma spark.

Reported in the Journal of Physics D: Applied Physics, the production of pure polymeric nitrogen—polynitrogen—is possible by zapping a compound called sodium azide with a jet of plasma in the middle of a super-cooling cloud of liquid nitrogen. The result is six nitrogen atoms bonded together—a compound called ionic, or neutral, nitrogen-six—that is predicted to be an extremely energy-dense material.

“Polynitrogen is being explored for use as a ‘green’ fuel source, for energy storage, or as an explosive,” said Danil Dobrynin, Ph.D., an associated research professor at the Nyheim Institute and lead author of the paper. “Versions of it have been experimentally synthesized—though never in a way that was stable enough to recover to ambient conditions or in pure nitrogen-six form. Our discovery using liquid plasma opens a new avenue for this research that could lead to a stable polynitrogen.”