Lifeboat Foundation

Engineers at the University of Pittsburgh are bringing concrete into the 21st century by reimagining its design. Concrete, which has its roots dating back to the Roman Empire, remains the most widely utilized material in the construction industry.

A new study presents a concept for the development of smart civil infrastructure systems with the introduction of metamaterial concrete. The research presents a concept for lightweight and mechanically-tunable concrete systems with integrated energy harvesting and sensing capabilities.

“Modern society has been using concrete in construction for hundreds of years, following its original creation by the ancient Romans,” said Amir Alavi, assistant professor of civil and environmental engineering at Pitt, who is the corresponding author on the study. “Massive use of concrete in our infrastructure projects implies the need for developing a new generation of concrete materials that are more economical and environmentally sustainable, yet offer advanced functionalities. We believe that we can achieve all of these goals by introducing a metamaterial paradigm into the development of construction materials.”

The NASA team hopes the iconic spacecraft and its twin can continue taking data beyond the solar system past their 50th birthdays.

Streacom and CALYOS are set to showcase the all-new fanless SG10 PC case at Computex 2023, which can passively cool and dissipate up to 600W.

The current work springs from a 2007 study in which Cavalleri and his team reported using terahertz laser pulses to distort a lattice into favoring a particular ground state [2]. The pulses excited specific, quantized vibrations—phonons—that changed the electronic state of a crystal, yielding a transient drop in electrical resistance of 5 orders of magnitude.

In their new experiment, the researchers selected three laser frequencies that were separately coupled to one of several possible lattice distortions in YTiO₃. Using a magneto-optical pump-probe setup, they examined how each of the excitations affected the crystal’s structure and its magnetism. Specifically, they observed whether the polarization of the light reflected by the crystal changed when viewed in opposite directions. A clockwise–counterclockwise shift in the polarization of the reflected light would be a sure sign of time-reversal invariance, which happens only in the presence of magnetic order.

They found that ultrafast laser pulses tuned to a phonon frequency of 9 THz caused the YTiO₃ crystal to fully magnetize just above zero K. They then showed that this order, instead of vanishing at 27 K, remained stable up to at least 80 K, the highest temperature that they measured. What’s more, the magnetism persisted for many nanoseconds, 6 orders of magnitude longer than the femtoseconds-long laser pulses. The team attribute this long-lasting state to the stability of the structural distortions induced by energy deposited by the laser.

With the power of the Gemini South Adaptive Optics Imager (GSAOI) on Gemini South, one half of the International Gemini Observatory, operated by NSF’s NOIRLab, astronomers have observed the first direct evidence of a dying star expanding to engulf one of its planets. Evidence for this event was found in a telltale “long and low-energy” outburst from a star in the Milky Way about 13,000 light-years from Earth. This event, the devouring of a planet by an engorged star, likely presages the ultimate fate of Mercury, Venus, and Earth when our sun begins its death throes in about five billion years.

“These observations provide a new perspective on finding and studying the billions of stars in our Milky Way that have already consumed their planets,” says Ryan Lau, NOIRLab astronomer and co-author on this study, which is published in the journal Nature.

“First of all, the environment has changed, and the need for more resilient energy transport methods for military operations is at a premium,” explained Col. Paul “Promo” Calhoun to Popular Mechanics in an exclusive interview. American forces operate globally like the special operations units he resupplied as a C-17 cargo pilot, from outposts in the South China Sea to the Iraqi desert. Since there is no simple way to power them, many forces use their radars, anti-drone microwave weapons, lasers, or other energy-intensive equipment. And with each passing year, the severity of the issue increases.

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The concept proposed by the team not only promises to reduce the operating cost of each system but also devise a way to store and transport liquified hydrogen, which is widely considered to be one of the primary sources of clean energy in the future. “The liquified hydrogen would be used to cool the superconductor guideway as it is stored and transported, reducing the need for a separate specialized pipeline system capable of cooling the fuel to 20 degrees Kelvin, or minus 424 Fahrenheit,” said a media release.

The conservation of energy is one of the most fundamental laws governing our reality. But in the expanding Universe, that’s just not true.

The quest to understand quantum mechanics has led to remarkable technological advancements, granting us power and control over the natural world. However, despite these successes, the paradoxes and mysteries surrounding the theory continue to challenge our understanding of reality. This raises the question of whether science, particularly quantum mechanics, provides us with true comprehension of the world or merely equips us with power without deeper understanding, writes John Horgan.