Sentences with phrase «by free electrons»

«At longer observing wavelengths, the source would be blurred by free electrons between us and the galactic center, and we wouldn't have enough resolution to see the predicted black hole shadow.

«Superradiance of an ensemble of nuclei excited by a free electron laser.»

Not exact matches

Because free radicals can create chain reactions by stealing electrons from the molecules that

Free radicals cause damage to cells by taking an electron away from a healthy

In our body, antioxidants like the ones in this blueberry, pomegranate and lemon popsicle neutralize the free radicals by donating an electron and in turn become oxidized themselves.

The way free radical do their damage is by carrying around one or more unpaired electrons, which makes them unstable.

Electrons thus accelerated could be wiggled by magnets to create a so - called free - electron laser (FEL), which generates exceptionally bright and brief flashes of x-rays that can illuminate short - lived chemical and biological phenomena.

There are basically two types of lines, those produced by collisions between the atoms or ions and the electrons in the surrounding gas, which are called collision lines, and which are very bright for elements such as oxygen, nitrogen and neon, and lines which are produced when ions capture free electrons, which are called recombination lines, and which are bright only for those gases with the highest abundances in the interstellar medium: hydrogen and helium.

For the first time, they managed to control the shape of the laser pulse to keep an electron both free and bound to its nucleus, and were at the same time able to regulate the electronic structure of this atom dressed by the laser.

Between 150 and 350 kilometers above Earth's surface, the density of free - floating electrons should drop by a factor of two as they rejoin atoms, the researchers say.

Since the 1980s, many experiments have tried to confirm the hypothesis advanced by the theorist Walter Henneberger: an electron can be placed in a dual state that is neither free nor bound.

A silicon crystal is doped by adding trace amounts of some other element that has either more free electrons than silicon's four (producing an electron surplus and making the result negative, or n - type) or fewer free electrons (producing a net electron deficit, and hence a positive, or p - type).

In this case, he was testing the idea that a buildup of cellular damage caused by oxidation — technically, the chemical removal of electrons from a molecule by highly reactive compounds, such as free radicals — is the main mechanism behind aging.

The research team headed by Prof. Jochen Küpper of the Hamburg Center for Free - Electron Laser Science (CFEL) choreographed a kind of molecular ballet in the X-ray beam.

The movement of free electrons and the gaps created by those loosed particles generate an electric current.

Waves of vibrating electrons, freed by ultraviolet light from the sun, seem to be why radar beams bounce off the upper atmosphere

The range of the measurement depth can be determined by measuring a physical quantity called the inelastic mean free path (IMFP), which defines how far an electron can travel in a material while retaining its original energy level in a statistical sense.

Their real breakthrough, however, is discovering the use of an intermediate dielectric coating (hafnium) to block the quenching of the free electrons in the metal by the CNTs, allowing the nanotubes to function uninhibited.

Last year, along with researchers led by Brookhaven / Columbia University School of Engineering physicist Simon Billinge, the team established the first firm link between the disappearance of the density wave within the pseudogap phase and the emergence, as stated by Davis, of «universally free - flowing electrons needed for unrestricted superconductivity» [see: https://www.bnl.gov/newsroom/news.php?a=11637].

As is demonstrated by the contrast between the wave functions of a free electron and those of a bound electron, the formation of bonds between particles doesn't so much collapse their wave function as localize it, by making it energetically improbable that a particle will exist outside a particular well of potential.

«We are demonstrating that when the electrons are no longer hampered by the «frozen» density wave state, they become universally free to flow unimpeded,» Davis said.

Despite existing in a solid and being surrounded by atoms, these electrons can sometimes behave just like free electrons, albeit with an «effective mass» that may be different than the free electron mass.

Elizabeth Heidrich, a PhD student at Newcastle University in England and lead author of the new study, studies microbial fuel cells — devices that generate electrical current by capturing the electrons freed as bacteria break down organic matter in wastewater.

Teeth and nails are good for measuring radiation because they pick up free radicals (atoms, or ions, with unpaired electrons) created by ionizing radiation and can retain them for long periods of time, says Harold Swartz, a Dartmouth Medical School professor of radiation oncology and director of the Dartmouth Biodosimetry Center for Medical Countermeasures against Radiation.

Researchers simulated the environment found inside these planets by creating shock waves in plastic with an intense optical laser at the Matter in Extreme Conditions (MEC) instrument at SLAC National Accelerator Laboratory's X-ray free - electron laser, the Linac Coherent Light Source (LCLS).

By 2016, Boeing is scheduled to transfer its free electron laser technology from Jefferson Laboratory and other participating labs, in order to demonstrate a 100 - kilowatt prototype that is compatible with operation on a ship.

This idyll has now been heavily shaken up by a team of physicists led by Matthias Kling, the leader of the Ultrafast Nanophotonics group in the Department of Physics at Ludwig - Maximilians - Universitaet (LMU) in Munich, and various research institutions, including the Max Planck Institute of Quantum Optics (MPQ), the Institute of Photonics and Nanotechnologies (IFN - CNR) in Milan, the Institute of Physics at the University of Rostock, the Max Born Institute (MBI), the Center for Free - Electron Laser Science (CFEL) and the University of Hamburg.

They were able to show that thin films have an intrinsic mechanism for dissociation of the strongly bound electron - hole pairs (excitons) to long - lived free - carriers provided by lower energy states at the edges of the layered perovskites.

This opens up new opportunities in the study of protein structures, as the team headed by DESY's Leading Scientist Henry Chapman from the Center for Free - Electron Laser Science reports in the Proceedings of the U.S. National Academy of Sciences (PNAS).

«If Earth's core consisted only of iron, the free electrons in the iron could handle the heat transport by themselves, without the need for any convection currents,» says Karsten Held.

The data were collected using the Linac Coherent Light Source X-ray free electron laser, or XFEL, at the SLAC National Accelerator Laboratory — operated by Stanford University for the U.S. Department of Energy Office of Science.

By combining two simple, inexpensive, metal - free catalysts, they sped the cell's slower reaction, taking protons and electrons derived from the hydrogen fuel and combining them with oxygen to pump out water, a reaction known as the oxygen reduction reaction.

The electrons remain at the center and are then free to do work, just like the electrons generated by fossil fuel combustion.

May 17 to 19, the campus will host «Big Mag @ UCSB,» a workshop intended to identify the transformational science that would be enabled by coupling a 32 Tesla superconducting magnet — about 1 million times stronger than the Earth's magnetic field — to UCSB's terahertz free - electron laser (FEL), the only facility of its kind in the U.S..

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free - Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and...

Normally, molecules are joined by strong covalent bonds in which the atoms share electrons, but in the chain they were instead linked by a freer mechanical bond.

These opportunities include using ultrafast X-ray sources to extract time - dependent structural information from proteins; and revolutionary possibilities created by X-ray Free Electron Laser radiation for an entirely new regime of pre-damage serial femtosecond crystallography.

These opportunities include the use of short - pulsed X-ray sources for extracting time - dependent structural information from proteins; and the revolutionary new possibilities created by X-ray Free Electron Lasers, which combine ultrafast X-ray pulses with high brilliance focussing capabilities to create an entirely new regime of pre-damage time - resolved serial femtosecond crystallography on unprecedented time - scales.

Here, we demonstrate that MISC is feasible at an X-ray free electron laser by studying the reaction of M. tuberculosisß - lactamase microcrystals with ceftriaxone antibiotic solution.

Free radical damage caused by electron - seeking, highly reactive, oxidative molecules has been identified as the source of many maladies through mechanisms such as inhibition of telomerase, changes to cellular permeability and DNA damage.

Free radicals are atoms which are defined by their possession of an unpaired electron.

Antioxidants help by providing «extra» electrons to free radicals, essentially stabilizing them and making them harmless.

Antioxidants neutralize free radicals by donating one of their own electrons, ending the electron - «stealing» reaction.

Healthy skin produces antioxidants that interfere with the process by which a free radical atom or molecule, which is missing an electron and is thus rendered unstable, attacks the nearest stable molecule and absconds with a replacement electron — a bit of thievery that results in damage to all components of a cell including DNA, proteins, lipids and its membrane.

They neutralize free radical damage by offering up one of their own electrons, thereby helping to prevent and repair cell and tissue breakdown that can result in further damage and disease — everything from wrinkles to hyperpigmentation.

These free radicals (such as: superoxide, hydroxyl radical, and peroxynitrite) are controlled by antioxidant systems and when these systems can't cope with the amount of free radicals produced these free radicals scavenge for electrons from proteins, cell membranes, and DNA.

Antioxidants neutralize free radicals by donating an electron, which ends the electron «stealing» reaction.

They also help reduce the formation of more free radicals or oxidative stress by quickly stabilizing the unpaired electrons.

Antioxidants come into the equation by stabilising these free radicals by donating an electron so they will no longer contain an unpaired electron anymore!

By giving electrons to free radicals, antioxidants can neutralize them, preventing them from causing harm.