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Dec 6, 2024

Hubble takes closest-ever look at a quasar

Posted by in categories: cosmology, materials

Astronomers have used the unique capabilities of NASA’s Hubble Space Telescope to peer closer than ever into the throat of an energetic monster black hole powering a quasar. A quasar is a galactic center that glows brightly as the black hole consumes material in its immediate surroundings.

The new Hubble views of the environment around the quasar show a lot of “weird things,” according to Bin Ren of the Côte d’Azur Observatory and Université Côte d’Azur in Nice, France. “We’ve got a few blobs of different sizes, and a mysterious L-shaped filamentary structure. This is all within 16,000 light-years of the black hole.”

Some of the objects could be small satellite galaxies around the black hole, and so they could offer the materials that will accrete onto the central super massive black hole, powering the bright lighthouse.

Dec 6, 2024

3D scans of giant hailstones reveal surprising discoveries that could help predict future storms

Posted by in categories: climatology, particle physics

Hailstones are formed during thunderstorms, when raindrops are propelled into very cold parts of a cloud, where they freeze. Once the particles are heavy enough, gravity pulls them back towards Earth. As they plummet, they grow into hailstones, which can cause injury to people and significant damage to homes and cars.

Scientists have been studying how hailstones grow since the 1960s but doing so meant breaking them in the process. To better understand the anatomy and growth of hailstones, researchers in Catalonia have used computed tomography (CT) scans to examine the giant hailstones that hit the north-east of the Iberian Peninsula during an exceptionally strong thunderstorm in the summer of 2022.

“We show that the CT scanning technique enables the observation of the internal structure of the hailstones without breaking the samples,” said Carme Farnell Barqué, a researcher at the Meteorological Service of Catalonia and lead author of the study published in Frontiers in Environmental Science.

Dec 6, 2024

Experiments provide evidence that interaction of light with a hydrocarbon molecule produces strained molecular rings

Posted by in categories: chemistry, solar power, sustainability

When molecules interact with ultraviolet (UV) light, they can change shape quickly, producing strain—stress in a molecule’s chemical structure due to an increase in the molecule’s internal energy. These processes typically take just tens of picoseconds (one millionth of a millionth of a second). Advanced capabilities at X-ray free electron laser (XFEL) facilities now enable scientists to create images of these ultrafast structural changes.

In work appearing in The Journal of Physical Chemistry A, researchers found structural evidence of a strained bicyclic molecule (a molecule consisting of two joined rings) that emerges from the chemical reaction that occurs when a cyclopentadiene molecule absorbs UV light. Cyclopentadiene is a good sample chemical for studying a range of reactions, and these findings have broad implications for chemistry.

Highly strained molecules have a variety of interesting applications in solar energy and pharmaceuticals. However, strain doesn’t typically occur naturally—energy must be added to a molecular system to create the strain. Identifying processes that produce molecules with strained rings is a challenge of broad interest in physical chemistry.

Dec 6, 2024

What can bees tell us about nearby pollution? The answer lies in their honey, a new study finds

Posted by in category: futurism

Inside every jar of honey is a taste of the local environment, its sticky sweet flavor enhanced by whichever nearby flowers bees have decided to sample. But a new study from Tulane University has found that honey can also offer a glimpse of nearby pollution.

The study, published in Environmental Pollution, tested 260 honey samples from 48 states for traces of six toxic metals: arsenic, lead, cadmium, nickel, chromium and cobalt. None of the honeys showed unsafe levels of toxic metals—based on a serving size of one tablespoon per day—and concentrations in the United States were lower than global averages.

However, researchers found in toxic metal distribution: the highest arsenic levels were found in honeys from a cluster of states in the Pacific Northwest (Oregon, Idaho, Washington and Nevada); the Southeast tested highest for cobalt levels, including Louisiana and Mississippi; and two of the three highest lead levels were found in the Carolinas.

Dec 6, 2024

X-ray data-enhanced computational method can determine crystal structures of multiphase materials

Posted by in categories: chemistry, computing, particle physics

A joint research team led by Yuuki Kubo and Shiji Tsuneyuki of the University of Tokyo has developed a new computational method that can efficiently determine the crystal structures of multiphase materials, powders that contain more than one type of crystal structures. The method can predict the structure directly from powder X-ray diffraction patterns, the patterns of X-rays passing through crystals roughly the same size as instant coffee particles.

Unlike conventional methods, this approach does not require the use of “lattice constants” and can be applied to existing experimental data that could not be analyzed until now. Thus, the new method is a crucial asset for discovering new material phases and developing new materials. The findings are published in The Journal of Chemical Physics.

Many materials can have several crystal structures, “phases,” even in the same solid state. Determining the underlying crystal structures of materials is essential for understanding their properties and formulating strategies to develop new materials. However, conventional methods make calculations using the “lattice constant,” a property of the crystal being investigated.

Dec 6, 2024

Researchers reveal the mechanism of runaway electron generation in tokamak fusion reactors

Posted by in categories: nuclear energy, particle physics

A research team has clarified the mechanism behind the generation of runaway electrons during the startup phase of a tokamak fusion reactor. The paper, “Binary Nature of Collisions Facilitates Runaway Electron Generation in Weakly Ionized Plasmas,” was published in the journal Physical Review Letters.

Nuclear energy refers to a power generation method that harnesses the energy of an artificial sun created on Earth, using resources extracted from seawater. To achieve this, technology capable of confining high-temperature plasma exceeding 100 million degrees for extended periods in a fusion is essential.

A tokamak is an artificial sun system in the shape of a torus, with no beginning or end, where magnetic fields are applied to confine particles.

Dec 6, 2024

Polarization photodetector that mimics desert ant offers pathway for more sensitive, miniaturized imaging systems

Posted by in categories: biotech/medical, computing

Polarization photodetectors (pol-PDs) have widespread applications in geological remote sensing, machine vision, and biological medicine. However, commercial pol-PDs usually require bulky and complicated optical components and are difficult to miniaturize and integrate.

Chinese researchers have made important progress in this area by developing an on-chip integrated polarization .

This study, published in Science Advances on Dec. 4, was conducted by Prof. Li Mingzhu’s group from the Technical Institute of Physics and Chemistry of the Chinese Academy of Sciences.

Dec 6, 2024

Emergence of steady quantum transport in a superconducting processor

Posted by in category: quantum physics

The use of quantum simulators for studying non-equilibrium quantum transport has been limited. Here the authors demonstrate the steady quantum transport between many-body qubit baths on a superconducting quantum processor, revealing insights into pure-state statistical mechanics for nonequilibrium quantum systems.

Dec 6, 2024

Scientists reveal superconductivity secrets of an iron-based material

Posted by in categories: engineering, particle physics, transportation

Scientists at the University of California, Irvine have uncovered the atomic-scale mechanics that enhance superconductivity in an iron-based material, a finding published recently in Nature.

Using advanced spectroscopy instruments housed in the UC Irvine Materials Research Institute, the researchers were able to image atom vibrations and thereby observe new phonons—quasiparticles that carry thermal energy—at the interface of an iron selenide (FeSe) ultrathin film layered on a (STO) substrate.

“Primarily emerging from the out-of-plane vibrations of oxygen atoms at the interface and in apical oxygens in STO, these phonons couple with electrons due to the spatial overlap of electron and phonon wave functions at the interface,” said lead author Xiaoqing Pan, UC Irvine Distinguished Professor of materials science and engineering, Henry Samueli Endowed Chair in Engineering and IMRI director.

Dec 6, 2024

Adults grow new brain cells — and these neurons are key to learning by listening

Posted by in category: neuroscience

Understanding how new neurons affect brain function throughout adulthood can offer new approaches to treating epilepsy and dementia.

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