Lifeboat Foundation

Supernovas might spell the end for the star they happen to, but they aren’t only destructive phenomena. When a star approaches the end of its life and runs out of fuel, it explodes in an enormous outpouring of energy, leaving behind a small, dense core that becomes a black hole or a neutron star. This explosion, though destructive on an epic scale, can also leave behind a beautiful remnant created by the explosion’s shock wave.

A image recently released by the Hubble Space Telescope team shows one such supernova remnant, called DEM L249. Captured by Hubble’s Wide Field Camera 3 instrument and located in the constellation of Mensa, this delicate structure is formed from dust and gas ejected outward from the star’s location by the force of the blast.

“This object — known as DEM L249 — is thought to have been created by a Type 1a supernova during the death throes of a white dwarf,” the Hubble scientists write. “While white dwarfs are usually stable, they can slowly accrue matter if they are part of a binary star system. This accretion of matter continues until the white dwarf reaches a critical mass and undergoes a catastrophic supernova explosion, ejecting a vast amount of material into space in the process.”

A new publication in Opto-Electronic Advances overviews dynamic metasurfaces and metadevices empowered by graphene.

Metasurfaces, artificial subwavelength structured interfaces, exhibit unprecedented capabilities to manipulate electromagnetic (EM) waves ranging from visible to terahertz and microwave frequencies.

In the past decade, static metasurfaces and metadevices have been researched extensively. Due to the passive nature of building blocks in general made of metals and/or dielectrics, however, their functionalities cannot be actively tuned in situ after fabrication, which seriously impedes their application scenarios such as varifocal lens, dynamic holography, and beam steering in LiDAR. Motivated by those significant requirements, scientists have struggled for years to improve the dynamical tunability of metasurfaces, and introducing active materials or components into the passive metasurfaces has been proposed as the first thought strategy.

Logic gates are the fundamental building blocks of computers, and researchers at the University of Rochester have now developed the fastest ones ever created. By zapping graphene and gold with laser pulses, the new logic gates are a million times faster than those in existing computers, demonstrating the viability of “lightwave electronics.”

Logic gates take two inputs, compare them, and then output a signal based on the result. They can, for example, output a 1 if both incoming signals are a 1 or a 0, or if either or neither of them is a 1, among other “rules.” Billions of individual logic gates are crammed into chips to create processors, memory and other electronic components.

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A team of researchers from China, Germany and the U.S. has developed a way to create a less fragile diamond. In their paper published in the journal Nature, the group describes their approach to creating a paracrystalline diamond and possible uses for it.

Prior research has shown that diamond is the hardest known material but it is also fragile—despite their hardness, diamonds can be easily cut or even smashed. This is because of their ordered atomic structure. Scientists have tried for years to synthesize diamonds that retain their hardness but are less fragile. The team has now come close to achieving that goal.

Currently, the way to create diamonds is to place a carbon-based material in a vice-like device where it is heated to very high temperatures while it is squeezed very hard. In this new effort, the researchers have used the same approach to create a less ordered type of diamond but have added a new twist—the carbon-based material was a batch of fullerenes, also known as buckyballs (carbon atoms arranged in a hollow spherical shape). They heated the material to between 900 and 1,300 °C at pressures of 27 to 30 gigapascals. Notably, the pressure exerted was much lower than is used to make commercial diamonds. During processing, the spheres were forced to collapse, and they formed into transparent paracrystalline diamonds which could be extracted at room temperature.

After launching our warehouse robot Stretch at #MODEX2022, we heard from a lot of warehouse and materials handling professionals. Check out our biggest takeaway… See more.

Launching Stretch, our autonomous warehouse robot, at MODEX 2022, we found consistent themes about the state of warehouse automation and material handling.

A team from the Tulane University School of Science and Engineering has developed a new family of two-dimensional materials that researchers say has promising applications, including in advanced electronics and high-capacity batteries.

Led by Michael Naguib, an assistant professor in the Department of Physics and Engineering Physics, the study has been published in the journal Advanced Materials.

“Two-dimensional materials are nanomaterials with thickness in the nanometer size (nanometer is one millionth of a millimeter) and lateral dimensions thousands of times the thickness,” Naguib said. “Their flatness offers unique set of properties compared to bulk materials.”

Creating a battery that can withstand repeated cycles of heating and cooling is no small feat. Temperature fluctuations cause the battery to expand and contract, and the researchers had to identify resilient materials that could tolerate these changes. “What we’ve seen before is a lot of active research to make sure you do not have to go through that thermal cycle,” says Vince Sprenkle, a strategic advisor in energy storage at PNNL and a co-author of the new paper. “We’re saying, ‘We want to go through it, and we want to be able to survive and use that as a key feature.’”

The result is a rechargeable battery made from relatively inexpensive materials that can store energy for extended periods. “It’s a great example of a promising long-duration energy-storage technology,” says Aurora Edington, policy director of the electricity industry association GridWise Alliance, who was not involved with this research. “I think we need to support those efforts and see how far we can take them to commercialization.”

The technology could be particularly useful in a place such as Alaska, where near-constant summer sunlight coincides with relatively low rates of energy use. A battery that can store energy for months could allow abundant summer solar power to fulfill winter electricity needs. “What is so attractive about the freeze-thaw battery is that seasonal shifting capability,” says Rob Roys, chief innovation officer at Launch Alaska, a nonprofit organization that works to accelerate the deployment of climate technologies in the state. Roys hopes to pilot the PNNL battery in a remote part of his state.

Admatec has steadily been increasing its 3D printing capabilities, taking its slurry-based digital light processing (DLP) process further. First it expanded from resins loaded with ceramic particles to those loaded with metal particles. It then increased the build volume of its Admaflex300 3D printer. Now, the company has introduced a new integrated debinding and sintering furnace with a larger work volume.

The majority of ceramic 3D printing processes rely on the use of a photopolymer slurry loaded with ceramic particles. Once printed, these green parts first go through a debinding process, in which the photopolymer material is removed, followed by sintering, causing the part to become fully dense.

Most craters are circular in shape due to material ejecting out in all directions as a result of an impact. Below is a group of impact craters in Noachis Terra, a large region in Mars’ southern hemisphere. These are all classified as simple craters, which are small bowl-shaped, smooth-walled craters.

Complex craters, on the other hand, are large craters with complicated features, such as terraces, central peaks, and rims and walls their own features. Oblong craters, like the one in the lead image — which is also located in Noachis Terra — can sometimes be created by impacts striking the surface at a very low grazing angle.