Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog – Page 1375

Researchers at EPFL have created the first detailed model explaining the quantum-mechanical effects that cause photoluminescence in thin gold films, a breakthrough that could advance the development of solar fuels and batteries.

Luminescence, the process where substances emit photons when exposed to light, has long been observed in semiconductor materials like silicon. This phenomenon involves electrons at the nanoscale absorbing light and subsequently re-emitting it. Such behavior provides researchers with valuable insights into the properties of semiconductors, making them useful tools for probing electronic processes, such as those in solar cells.

In 1969, scientists discovered that all metals luminesce to some degree, but the intervening years failed to yield a clear understanding of how this occurs. Renewed interest in this light emission, driven by nanoscale temperature mapping and photochemistry applications, has reignited the debate surrounding its origins. But the answer was still unclear – until now.

Read more | >

Researchers have discovered an extraordinary metal alloy that won’t crack at extreme temperatures due to kinking, or bending, of crystals in the alloy at the atomic level.

A metal alloy composed of niobium, tantalum, titanium, and hafnium has shocked materials scientists with its impressive strength and toughness at both extremely hot and cold temperatures, a combination of properties that seemed so far to be nearly impossible to achieve. In this context, strength is defined as how much force a material can withstand before it is permanently deformed from its original shape, and toughness is its resistance to fracturing (cracking). The alloy’s resilience to bending and fracture across an enormous range of conditions could open the door for a novel class of materials for next-generation engines that can operate at higher efficiencies.

The team, led by Robert Ritchie at Lawrence Berkeley National Laboratory (Berkeley Lab) and UC Berkeley, in collaboration with the groups led by professors Diran Apelian at UC Irvine and Enrique Lavernia at Texas A&M University, discovered the alloy’s surprising properties and then figured out how they arise from interactions in the atomic structure. Their work is described in a study recently published in the journal Science.

Read more | >

Over the course of nearly two decades, its powerful radar provided never-before-seen details of clouds and helped advance global weather and climate predictions.

CloudSat, a NASA mission that peered into hurricanes, tallied global snowfall rates, and achieved other weather and climate firsts, has ended its operations. Originally proposed as a 22-month mission, the spacecraft was recently decommissioned after almost 18 years observing the vertical structure and ice/water content of clouds.

As planned, the spacecraft — having reached the end of its lifespan and no longer able to make regular observations — was lowered into an orbit last month that will result in its eventual disintegration in the atmosphere.

Read more | >

Materials that are incredibly thin, only a few atoms thick, exhibit unique properties that make them appealing for energy storage, catalysis, and water purification. Researchers at Linköping University, Sweden, have now developed a method that enables the synthesis of hundreds of new 2D materials. Their study has been published in the journal Science.

Since the discovery of graphene, the field of research in extremely thin materials, so-called 2D materials, has increased exponentially. The reason is that 2D materials have a large surface area in relation to their volume or weight. This gives rise to a range of physical phenomena and distinctive properties, such as good conductivity, high strength or heat resistance, making 2D materials of interest both within fundamental research and applications.

Read more | >

Explorations in dark matter are advancing with new experimental techniques designed to detect axions, leveraging advanced technology and interdisciplinary collaboration to uncover the secrets of this elusive component of the cosmos.

A ghost is haunting our universe. This has been known in astronomy and cosmology for decades. Observations suggest that about 85% of all the matter in the universe is mysterious and invisible. These two qualities are reflected in its name: dark matter.

Several experiments have aimed to unveil what it’s made of, but despite decades of searching, scientists have come up short. Now our new experiment, under construction at Yale University in the US, is offering a new tactic.

Read more | >

Researchers discovered ferroelectricity in 2D vermiculite, boosting electric field responsivity in liquid crystals and paving the way for innovative large-scale displays.

Electro-optical liquid crystal (LC) device with wide applications is a cornerstone of the information society, which can continuously and dynamically modulate the light intensity, polarization, and phase retardation. An ancient theoretical insight proposes that a LC material with both an extremely large geometrical anisotropy and an inherent electric dipole is highly expected to improve the electric field responsivity of LCs.

However, neither commercial organic LC molecules nor R&D LC nanomaterials meet both aforementioned perquisites, while such LCs have not been reported so far. As for now, they are open questions for LC community about whether such an LC exists and the upper limit of its electric field responsivity.

Read more | >

Researchers utilizing the European Gaia spacecraft have discovered a black hole in a binary system, located 1,500 light-years away and weighing 33 times the mass of the sun, making it the heaviest known in the Milky Way.

The black hole, discovered using data from the European Gaia spacecraft, is more than three times heavier than the known black holes in our galaxy.

An international team of researchers, with the participation of researchers from Tel Aviv University (TAU) led by Prof. Tsevi Mazeh, discovered a star that orbits a black hole 33 times heavier than the sun’s mass, and lies 1,500 light-years away from Earth. The black hole, discovered using data from the European Gaia spacecraft, is more than three times heavier than the other known black holes in our galaxy.

Read more | >

Peptides can form on cosmic dust despite water presence, challenging previous beliefs and suggesting a possible extraterrestrial origin for life’s building blocks.

Peptides are organic compounds that play a crucial role in many biological processes, for example, as enzymes. A research team led by Dr. Serge Krasnokutski from the Astrophysics Laboratory at the Max Planck Institute for Astronomy at the University of Jena had already demonstrated that simple peptides can form on cosmic dust particles. However, it was previously assumed that this would not be possible if molecular ice, which covers the dust particle, contains water – which is usually the case.

Now, the team, in collaboration with the University of Poitiers, France, has discovered that the presence of water molecules is not a major obstacle for the formation of peptides on such dust particles. The researchers report on their findings in the journal Science Advances.

Read more | >

Meta presents AdvPrompter Fast Adaptive Adversarial Prompting for LLMs.

Meta presents AdvPrompter.

Fast Adaptive Adversarial Prompting for LLMs https://huggingface.co/papers/2404.

While recently Large Language Models (LLMs) have achieved remarkable successes, they are vulnerable to certain jailbreaking attacks that lead to generation of inappropriate or harmful…

Continue reading “AdvPrompter: Fast Adaptive Adversarial Prompting for LLMs” | >