Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: particle physics – Page 294

Researchers propose a simple, inexpensive approach to fabricating carbon nanotube wiring on plastic films

Carbon nanotubes (CNTs) are cylindrical tube-like structures made of carbon atoms that display highly desirable physical properties like high strength, low weight, and excellent thermal and electrical conductivities. This makes them ideal materials for various applications, including reinforcement materials, energy storage and conversion devices, and electronics.

Despite such immense potential, however, there have been challenges in commercializing CNTs, such as their incorporation on plastic substrates for fabricating flexible CNT-based devices. Traditional fabrication methods require carefully controlled environments such as high temperatures and a clean room. Further, they require repeat transfers to produce CNTs with different resistance values.

More direct methods such as laser-induced forward transfer (LIFT) and thermal fusion (TF) have been developed as alternatives. In the LIFT method, a laser is used to directly transfer CNTs onto substrates, while in TF, CNTs are mixed with polymers that are then selectively removed by a laser to form CNT wires with varying resistance values.

Reaching superconductivity layer

Imagine a sheet of material just one layer of atoms thick—less than a millionth of a millimeter. While this may sound fantastical, such a material exists: it is called graphene and it is made from carbon atoms in a honeycomb arrangement. First synthesized in 2004 and then soon hailed as a substance with wondrous characteristics, scientists are still working on understanding it.

Postdoc Areg Ghazaryan and Professor Maksym Serbyn at the Institute of Science and Technology Austria (ISTA) together with colleagues Dr. Tobias Holder and Professor Erez Berg from the Weizmann Institute of Science in Israel have been studying for years and have now published their newest findings on its superconducting properties in a research paper in the journal Physical Review B.

“Multilayered graphene has many promising qualities ranging from widely tunable band structure and special optical properties to new forms of superconductivity—meaning being able to conduct electrical current without resistance,” Ghazaryan explains.

Breakthrough in Quantum Chemistry: Tunnel Effect Experimentally Observed in Molecules

While tunneling reactions are remarkably hard to predict, a group of researchers were able to experimentally observe such an effect, marking a breakthrough in the field of quantum chemistry.

Tunnel Effect

Predicting tunnel effects is very difficult to pull off. The mechanically exact quantum description of chemical reactions that cover over three particles is quite hard. If it covers over four particles, it is almost impossible to pull off. In order to stimulate the reactions, scientists use classical physics but have to push aside the quantum effects. However, EurekAlert reports that there is a limit to classically describing these chemical reactions. What, then, is the limit?

New liquid nitrogen spray could help NASA solve its lunar dust problem

The novel method could form a crucial part of NASA’s plans to establish a permanent human presence on the moon.

You may not know that lunar dust poses a real problem to NASA as it aims to establish a permanent crew presence on the moon with its upcoming Artemis missions.

Now, though, a new liquid nitrogen spray developed by Washington State University researchers was able to remove virtually all of the simulated moon dust from a space suit during tests, a press statement reveals.

NASA

Moondust is largely made of small particles that can damage spacesuits, machinery, and equipment. In future habitats, it may even pose a health risk by damaging astronauts’ lungs.

Continue reading “New liquid nitrogen spray could help NASA solve its lunar dust problem” | >

NASA sheds light on a massive supernova dating back to Middle Ages

The supernova is so old that it is believed to have been described in a passage of Shakespeare’s “Hamlet.”

A group of scientists has shed new light on a star that exploded in a supernova more than 450 years ago, blasting particles out into space at close to the speed of light.

Now, astronomers have used NASA’s Imaging X-ray Polarimetry to study the incredibly long-lasting aftereffects of the supernova called Tycho.

NASA/ASI/MSFC/INAF/R. Ferrazzoli, et al.

The Tycho supernova blast released as much energy as the Sun would emit over ten billion years, NASA pointed out in a statement. The blast was visible to many humans on Earth way back in 1572.

Quantum chemistry: Molecules caught tunneling

Tunneling reactions in chemistry are difficult to predict. The quantum mechanically exact description of chemical reactions with more than three particles is difficult, with more than four particles it is almost impossible. Theorists simulate these reactions with classical physics and must neglect quantum effects. But where is the limit of this classical description of chemical reactions, which can only provide approximations?

Roland Wester from the Department of Ion Physics and Applied Physics at the University of Innsbruck has long wanted to explore this frontier. “It requires an experiment that allows very and can still be described quantum-mechanically,” says the experimental physicist. “The idea came to me 15 years ago in a conversation with a colleague at a conference in the U.S.,” Wester recalls. He wanted to trace the quantum mechanical tunnel effect in a very simple reaction.

Since the tunnel effect makes the reaction very unlikely and thus slow, its experimental observation was extraordinarily difficult. After several attempts, however, Wester’s team has now succeeded in doing just that for the first time, as they report in the current issue of the journal Nature.

Observing phononic skyrmions based on the hybrid spin of elastic waves

Skyrmions are extremely small with diameters in the nanoscale, and they behave as particles suited for information storage and logic technologies. In 1961, Tony Skyrme formulated a manifestation of the first topological defect to model a particle and coined it as skyrmions. Such particles with topologically stable configurations can launch a promising route toward establishing high-density magnetic and phononic (a discrete unit of quantum vibrational mechanical energy) information processing routes.

In a new report published in Science Advances, Liyun Cao and a team of researchers at the University of Lorraine CNRS, France, experimentally developed phononic skyrmions as new topological structures by using the three-dimensional (3D) hybrid spin of . The researchers observed the frequency-independent spin configurations and their progression toward the formation of ultra-broadband phononic skyrmions that could be produced on any solid structure.

Water is Behind the Electrification of Sand

The results of new experiments indicate that surface-adsorbed water molecules are responsible for contact electrification in granular matter, a finding that challenges established models of this phenomenon.

When two surfaces come into contact, they can exchange electrical charge. This fundamental phenomenon is linked to some of humankind’s earliest scientific experiments—reports suggest that the ancient Greeks uncovered static electricity after rubbing various materials together. Numerous physical processes are at play when two objects touch. But the mechanism underpinning charge exchange—which is known as contact electrification—has bedeviled scientists for centuries [1]. New experiments by Galien Grosjean and Scott Waitukaitis of the Institute of Science and Technology Austria now bring welcome clarity in this field [2]. By levitating a single particle and measuring its charge after consecutive collisions with a surface, the researchers were able to uncover a connection between contact electrification and water molecules on the particle and the surface.

When large numbers of insulating particles, such as grains of sand or particles of flour, collide or rub past each other, enormous electric potentials can build up. Such potentials can have dramatic consequences, leading to spectacular discharges, such as the lightning flashes seen during a sandstorm or a volcanic-ash eruption. Closer to home, such discharges can ignite flammable dusts or disrupt powder flows [3, 4]. But a mystery surrounds this contact electrification: How can identical particles exchange charge? In other words, Why does one of the particles become a donor of charge and the other an acceptor?

Largest Structures in the Universe Contain Magnetic Fields That Shed Light on Cosmic Web Formation

Magnetic fields abound in the universe. Despite the fact that the Universe is electrically neutral, atoms may be ionized into positively and negatively charged nuclei and electrons.

According to Science Alert, magnetic fields are created when charges are accelerated. Collisions between and inside interstellar plasma are one of the most prevalent sources of large-scale magnetic fields. This is one of the primary generators of magnetic fields at the cosmic scale.