Новости за 30.04.2021

The microscopic structures and properties of materials are intimately linked, and customizing them is a challenge. Rice University engineers are determined to simplify the process through machine learning.

Global sea level rise associated with the possible collapse of the West Antarctic Ice Sheet has been significantly underestimated in previous studies, meaning sea level in a warming world will be greater than anticipated, according to a new study from Harvard researchers.

The detection of the axion would mark a key episode in the history of science. This hypothetical particle could resolve two fundamental problems of Modern Physics at the same time: the problema of Charge and Parity in the strong interaction, and the mystery of dark matter. However, in spite of the high scientific interest in finding it, the search at high radio frequency—above 6 GHz—has been almost left aside for the lack of the high sensitivity technology which could be built at reasonable cost. Читать дальше...

Chemical organization in reaction-diffusion systems offer a strategy to generate materials with ordered morphologies and architecture. Periodic structures can be formed using molecules or nanoparticles. An emerging frontier in materials science aims to combine nanoparticles and molecules. In a new report on Science Advances, Amanda J. Ackroyd and a team of scientists in chemistry, physics and nanomaterials in Canada, Hungary and the U.S. noted how solvent evaporation from a suspension of cellulose... Читать дальше...

Methane is not the most abundant greenhouse gas in our atmosphere, but it is among the most potent. Roughly a quarter of global methane emissions come from natural sources, and freshwater ecosystems are the largest source of atmospheric methane. Most of the data on methane dynamics in aquatic ecosystems come from boreal and temperate environments. Less is known about the fate of methane in tropical lakes.

A dynamo mechanism could explain the incredibly strong magnetic fields in white dwarf stars according to an international team of scientists, including a University of Warwick astronomer.

According to classical electromagnetism, a charged particle moving in an external magnetic field experiences a force that makes the particle's path circular. This basic law of physics are exploited in designing cyclotrons that work as particle accelerators. When nanometer-size metal particles are placed in a magnetic field, the field induces a circulating electron current inside the particle. The circulating current in turn creates an internal magnetic field that opposes the external field. This physical effect is called magnetic shielding.

The guilty verdicts delivered against Derek Chauvin on April 20, 2021, represented a landmark moment—but courtroom justice cannot deliver the sweeping changes most Americans feel are needed to improve policing in the U.S.

Advanced X-ray techniques have revealed new structural details about the specific arrangement of atoms in conjugated polymers, an important class of materials that are used in LEDs, organic solar cells, transistors, sensors and thermoelectric power devices.

An article published in the journal Nature Geoscience has highlighted the shocking under-representation of students from ethnic minority backgrounds in the Geosciences.

CERN's Large Hadron Collider (LHC) is famous for colliding protons at world-record energies—but sometimes it pays to dial down the energy and see what happens under less extreme conditions. The LHC started operation in 2010 with a collision energy of 7 TeV, and ran at 13 TeV from 2015 to 2018. But for one week in 2017, the LHC produced moderate-intensity collisions at only 5 TeV—allowing scientists to analyze the production of various elementary particles at a lower collision energy.

The future of particle acceleration has begun. Awake is a promising concept for a completely new method with which particles can be accelerated even over short distances. The basis for this is a plasma wave that accelerates electrons and thus brings them to high energies. A team led by the Max Planck Institute for Physics now reports a breakthrough in this context. For the first time, they were able to precisely time the production of the proton microbunches that drive the wave in the plasma. This... Читать дальше...

An international team of researchers has found evidence showing that forest regrowth in Amazonia began prior to the arrival of Europeans in South America. In their paper published in the journal Science, the group describes their analysis of fossilized pollen retrieved from lake beds in the region.

Three teams working independently have found evidence that suggests the Z-genome in bacteria-invading viruses is much more widespread than thought. All three of the groups have used a variety of genomic techniques to identify parts of the pathways that lead development of the Z-genome in bacteria-invading viruses known as bacteriophages. The first team was made up of researchers from several institutions in China and one in Singapore, the second with members from several institutions in France; the third was an international effort. Читать дальше...

The carbon-oxygen (C-O) bond in alkyl ethers can be cleaved using mild methods to simplify chemical syntheses by elaborating robust, readily available precursors. In a new report now on Science, Hairong Lyu and a research team in chemistry at the University of Chicago and the University of Pittsburgh, U.S. detailed how dibromoboranes reacted with alkyl ethers in the presence of a nickel (Ni) catalyst and zinc reductant to insert boron into the C-O bond. The subsequent reactivity affected the oxygen-to-nitrogen... Читать дальше...

Heavy rains poured down on the island of St. Vincent and the Grenadines on Thursday, causing flooding and mudslides that damaged some homes and further battered areas already burdened by heavy ashfall from eruptions of La Soufriere volcano.

New research indicates that the computer-based models currently used to simulate how Earth's climate will change in the future underestimate the impact that forest fires and drying climate are having on the world's northernmost forests, which make up the largest forest biome on the planet. It's an important understanding because these northern forests absorb a significant amount of Earth's carbon dioxide.