Lancaster University chemists in collaboration with international colleagues have uncovered a'Crystal Nuclei Breeding Factory'which, they say,
#Tiny terahertz accelerator could rival huge free-electron lasers Physicists in the US, Germany and Canada have built a miniature particle accelerator that uses terahertz radiation instead of radio waves to create pulses of high-energy electrons.
A single accelerator module of the prototype is just 1. 5 cm long and 1 mm thick,
Potential applications include free-electron lasers, whereby the electrons are used to create coherent pulses of X-rays.
However, the team cautions that much more work is needed to develop the technology so it can be used in medicine,
and microwaves are used to accelerate charged particles. In this latest work Emilio Nanni and colleagues at the Massachusetts institute of technology (MIT), the Center For free-Electron Laser Science (CFEL) at DESY in Germany and the University of Toronto have created a terahertz accelerator module with the aim
of advancing experiments that use ultrafast electron diffraction to reveal the structure and dynamics of matter.
Their prototype accelerator uses optically generated pulses centred at 450 GHZ and a bandwidth of 20000 GHZ.
Steep gradients The terahertz accelerator module increased the energy of electrons fired into it by 7 kev.
and cost of accelerators and improve the quality of the electron beams they produce.""Steven Jamison of the UK's Accelerator Science and Technology Centre (ASTEC), who wasn't involved in the research,
it is an important first step to obtaining relativistic energy electrons with terahertz waves.""More power needed The main barrier to faster accelerating gradients is the power of terahertz pulses that can be generated."
The researchers now plan to focus on developing a free-electron laser (FEL) based on terahertz technology,
FELS fire high-speed electrons down an undulating path, which causes them to emit intense flashes of X-ray light.
and work out how Alice is encoding a series of photons sent to her by Bob that will constitute the secret key.
if Alice sets up a detector to measure the energy of the incoming photons, which sounds an alarm
"Alice and Bob share a key encoded using photon polarization, while Eve inserts a device into the polarized beam that very slightly tilts the beam
which detectors are used to measure which photons, and by doing so to steal the key unnoticed.
Superfluids are thought to flow endlessly, without losing energy, similar to electrons in a superconductor. Observing the behavior of superfluids
Atoms of rubidium are known as bosons, for their even number of nucleons and electrons. When cooled to near absolute zero
bosons form what called a Bose-Einstein condensate a superfluid state that was discovered first co by Ketterle,
and for which he was awarded ultimately the 2001 Nobel prize in physics. After cooling the atoms,
which mimics the regular arrangement of particles in real crystalline materials. When charged particles are exposed to magnetic fields,
their trajectories are bent into circular orbits, causing them to loop around and around. The higher the magnetic field, the tighter a particle orbit becomes.
However, to confine electrons to the microscopic scale of a crystalline material, a magnetic field 100 times stronger than that of the strongest magnets in the world would be required.
The group asked whether this could be done with ultracold atoms in an optical lattice. Since the ultracold atoms are charged not,
as electrons are, but are instead neutral particles, their trajectories are unaffected normally by magnetic fields. Instead, the MIT group came up with a technique to generate a synthetic
ultrahigh magnetic field, using laser beams to push atoms around in tiny orbits, similar to the orbits of electrons under a real magnetic field.
In 2013, Ketterle and his colleagues demonstrated the technique, along with other researchers in Germany, which uses a tilt of the optical lattice
In this scenario, atoms could only move with the help of laser beams. ow the laser beams could be used to make neutral atoms move around like electrons in a strong magnetic field
or loop around, in a radius as small as two lattice squares, similar to how particles would move in an extremely high magnetic field. nce we had the idea,
This expansion and contraction of aluminum particles generates great mechanical stress, which can cause electrical contacts to disconnect.
which would be ok if not for the repeated large volume expansion and shrinkage that cause SEI particles to shed.
but yolk-shell particles feature a void between the two equivalent to where the white of an egg would be.
The aluminum particles they used, which are about 50 nanometers in diameter, naturally have oxidized an layer of alumina (Al2o3).
a better conductor of electrons and lithium ions when it is very thin. Aluminum powders were placed in sulfuric acid saturated with titanium oxysulfate.
if the particles stay in the acid for a few more hours, the aluminum core continuously shrinks to become a 30-nm-across olk,
The particles are treated then to get the final aluminum-titania (ATO) yolk-shell particles. After being tested through 500 charging-discharging cycles,
and electrons to get in and out. The result is an electrode that gives more than three times the capacity of graphite (1. 2 Ah/g) at a normal charging rate
indicating ATO is quite close to being ready for real applications. hese yolk-shell particles show very impressive performance in lab-scale testing,
e transferred electrons from the dopant potassium to the surface of the black phosphorus, which confined the electrons
and allowed us to manipulate this state. Potassium produces a strong electrical field which is required what we to tune the size of the band gap. his process of transferring electrons is known as doping
and induced a giant Stark effect, which tuned the band gap allowing the valence and conductive bands to move closer together,
The electrolyte in such batteries typically a liquid organic solvent whose function is to transport charged particles from one of a battery two electrodes to the other during charging
says Schwab. e all know quantum mechanics explains precisely why electrons behave weirdly. Here, wee applying quantum physics to something that is relatively big,
Some have used tiny particles of glass, melded together at a lower temperature in a technique called sintering.
and excel at transmitting electrons and heat. But when the two are joined, the way the atoms are arranged can influence all those properties. ome labs are actively trying to make these materials or measure properties like the strength of single nanotubes and graphene sheets,
which a beam of electrons smaller than the size of a hydrogen atom is scanned over a sample
and measures how many electrons interact with the atoms at each scan position. The method reveals the atomic structure of materials
because different arrangements of atoms cause electrons to interact in different ways. However scanning transmission electron microscopes only produce two-dimensional images.
The downside of this technique is repeated that the electron beam radiation can progressively damage the sample.
thanks to the electron beam energy being kept below the radiation damage threshold of tungsten. Miao and his team showed that the atoms in the tip of the tungsten sample were arranged in nine layers, the sixth
The nanoparticle hydrophilic layer essentially locks in the active ingredient, a hydrophobic chemical called padimate O. Some sunscreen solutions that use larger particles of inorganic compounds, such as titanium dioxide or zinc oxide,
like a dust particle, to start the process of nucleation, the bubbles formed by boiling water also require nucleation.
Electrons are able to travel though it without resistance at room temperature, promising a new approach to electronics.
and starting the flow of electrons, thus offering an alternative to silicon in electronics. Despite these properties,
In ordinary materials, electrons repel each other, but in superconductors the electrons form pairs known as Cooper pairs,
which together flow through the material without resistance. Phonons, the mechanism that facilitates these electronsalliances are vibrations in lattice crystalline structures.
could contribute a lot of phonons to the graphene electrons. In a research paper available on arxiv, the researchers demonstrated in physical experiments that the computer models were indeed correct in their predictions.
the researchers found that the electrons slowed down as they travelled through the lattice, which they believe to be the result of enhanced electronhonon coupling.
which the researchers measured by identifying an energy gap between the material's conducting and nonconducting electrons.
believe this latest work could usher in the fabrication of nanoscale superconducting quantum interference devices and single-electron superconductor quantum dots u
The resulting force on electrons causes them to migrate to the side, which in turn raises a voltage perpendicular to the flow of current.
the fundamental charge of the electron and a quantum mechanical measure dubbed the Planck constant.
Researchers have suspected long that the unique behavior of electrons in graphene, namely the big spacing between electron energy levels when the material is exposed to a magnetic field,
could be exploited to produce precise measurements of resistance under less extreme physical conditions. Several recent results support that idea.
this unit of current will be redefined in terms of the fundamental charge of the electron, and quantum electrical standards will play a closer, more integrated role.
which involves exploiting the oscillations in the density of electrons that are generated when photons hit a metal surface.
The researchers applied the experimental spectroscopy technique to examine hydrogen absorption in single palladium nanoparticles.
In that way, the gained fundamental understanding of the reasons underlying the differences between seemingly identical individual particles
or impacting them in some other way that eliminates the ability to observe them accurately. hen studying individual nanoparticles you have to send some kind of probe to ask the particle hat are you doing?
said Langhammer. his usually means focusing a beam of high-energy electrons or photons or a mechanical probe onto a very tiny volume.
In contrast to non-polarized light, in which the electric fields of the photons are oriented in random directions,
The nanowires create a sea of electrons that produces lasmondensity waves, the oscillations in the density of electrons that are generated
when photons hit a metal surface. These plasmon density waves absorb energy from the photons that pass through the silicon wafer.
The absorption of the energy produces otor energetic electrons, which generate a detectable electrical current.
The researchers found that they could make the zigzag pattern of nanowires with a right-or left-handed orientation.
When they arranged the nanowires in right-handed pattern, the surface absorbed right circularly polarized light
These devices take advantage of the ability of electrons to penetrate barriers, a phenomenon known as quantum tunneling.
The amount of energy the accelerator can pump into a cluster of particles electrons, for example,
thus becomes a function of the device gradient and length. And cost, of course, increases with physical size of the accelerator.
These machines accelerate charged particles using either a pulse of radio frequency radiation or a wakefield (using high energy unchesof electrons to blast a tunnel through plasma;
when the tunnel collapses back on itself, following particles accelerate by riding the charged wake of the collapsing front).
RF accelerators can reach energies of a few tens of mega electron volts before the RF energy itself begins to destabilize the mechanism in what called plasma breakdown.
and the Deutsches Electronen Synchrotron (DESY, the German Electron Syncrotron), the Center For free-Electron Laser Science (CFEL), the Max Planck Institute for Structure and Dynamics,
and accommodate a significant amount of charge per bunch of electrons On the other hand, the frequency is high enough that the plasma breakdown threshold for surface electric fields increases The terahertz approach also allows them to use readily available picoseconds lasers.
electrons are injected at 60 kev through a pinhole at the left end. When the terahertz pulse reflects off the left wall (around the injection pinhole) it catches the electrons,
accelerating them back towards the right. In the initial experiments, the electrons could ride the wave for just 3 mm before the wave started to spread out.
That short ride however, boosted their energy to 67 kev. A back of the envelope calculation translates this modest energy gain into an acceleration gradient over 2 Mev/m. his is not a particularly large acceleration,
his proof-of-principle terahertz linear accelerator demonstrates the potential for an all-optical acceleration scheme that can be integrated readily into small-scale laboratories providing users with electron beams that will enable new experiments in ultrafast electron diffraction and X-ray production
In research published in the journal Nature Communications, the RIKEN scientists discovered that the wrinkles found in graphene create unique electronic qualities, specifically a one-dimensional electron confinement.
This restriction of electron movement results in a junction-like structure that changes from a zero-gap conductor to a semiconductor and back to zero-gap conductor.
It consists of a barebones web app that can be used as the nucleus of new game designs or alternative applications.
and their spacing within the lattice can strengthen interactions between electrons that cause superconductivity. TOKYO:
and their spacing within the lattice can strengthen interactions between electrons that cause superconductivity i
and converts to electrons. Those electrons then supplement the voltage stored in the lithium-anode portion of the solar battery.
To carry electrons from the solar cell into the battery a liquid electrolyte is required, which is typically part salt, part solvent.
The researchers used lithium iodide as the salt, which offers a high-energy storage capacity with low cost,
and converts to electrons. Those electrons then supplement the voltage stored in the lithium-anode portion of the solar battery.
To carry electrons from the solar cell into the battery a liquid electrolyte is required, which is typically part salt, part solvent.
The researchers used lithium iodide as the salt, which offers a high-energy storage capacity with low cost,
That creates particles that crystallize into diamonds, a process that can take 10 weeks. The technology has progressed to the point that experts need a machine to tell synthesized gems apart from those extracted from mines or rivers.
"We're good at generating electrons from light efficiently, but chemical synthesis always limited our systems in the past,
and particle diffusion. To address the problem, the team of researchers, led in part by Thomas Angelini,
assistant professor in the department of mechanical and aerospace engineering at the University of Florida, took advantage of the physical properties of a commercially available granular hydrogel made up of 7 m-wide particles.
These PDA particles capture pore-forming toxins such as those found in bee venom. Chen and Wang successfully discovered that the strong swimming mechanisms of their microfish actually enhanced the ability to clear up toxins,
The printer works by directing an electron beam at a bed of titanium powder in order to melt it.
and particle diffusion, the study authors explained, nd enables a wide variety of materials to be written by this process,
Other applications include tissue engineering, flexible electronics, particle engineering, smart materials, and encapsulation technologies. In order to demonstrate the possibilities of this new 3d printing method,
similar to an ultrasound scanner but for manipulating particles (that is, drug capsules, kidney stones or microsurgical instruments),
also, single-beam traps do not have repeated patterns that could accidentally trap other particles.""Professor Drinkwater said the development could also lead to"non-contact production lines"for handling delicate or dangerous materials without contact.
It was thought previously that progerin did so through causing the nucleus to be deformed, thereby weakening the ability of cells to divide
and that, in turn, changes the frequency at which the protons in water molecules around and inside the gel resonate in response to radio-frequency radiation.
For example, transmission electron micrographs of a three-dimensional, nanoscale humanoid robot confirm that the pieces fit together exactly as designed.
which the light-emitting particles are sandwiched in a dielectric binder layer. At least one of the conductive layers is also transparent.
On application of an AC voltage, light is emitted from the electroluminescent layer. e embed luminous particles in the form of functionalized zinc sulphide nanoparticles as phosphors into the binder layer,
#Cerium-Based Material Made into Nanometer-Sized Particles to Produce Key Ingredient for Nylon Production The Critical Materials Institute,
The process uses a cerium-based material made into nanometer-sized particles with a palladium catalyst to produce cyclohexanone, a key ingredient in the production of nylon.
#Groundbreaking Work with Two-Photon Microscopy Wins Brain Prize The 1 million euro Brain Prize has been awarded to four scientists three of them Cornell alumni for their groundbreaking work with two
-photon microscopy: Winfried Denk, Ph d. 9, Karel Svoboda 8, David Tank, M. S. 0, Ph d. 3 and Arthur Konnerth.
Zipfel still has the world first two-photon microscope in a case near his office,
Denk took the first two-photon microscopy images with the help of Frank Wise, the Samuel B. Eckert Professor of Engineering,
who built the femtosecond laser needed to make two-photon microscopy work. Solving the mystery of how circuits in the brain produce behavior,
Two-photon microscopy is a transformative tool in brain research, combining advanced techniques from physics and biology to allow scientists to examine the finest structures of the brain in real time. ee very proud of the work these alumni are doing,
and laser scanning microscopes, X-ray microscopes, electron and ion microscopes and spectrometer modules. Users are supported for software for system control, image capture and editing.
which involves a material giving up electrons and transporting ions through another material at the interface between electrode and electrolyte.
"Moreover, the conductive Fe-Ni core provides a highway to accelerate the transport of electrons to the current collector,
Hansman's research team recently discovered that a"nanobody"called Nano-85 was able to bind to intact norovirus-like particles (VLPS) in culture.
"Interestingly, the investigators found that the site where Nano-85 bound to the P domain was hidden actually under the viral particle's surface."
which measures the interaction of photons with an activated surface using nanostructures in order to do chemical and biological sensing.
when releasing lithium. his expansion and contraction of aluminum particles generates great mechanical stress, which can cause electrical contacts to disconnect.
which would be ok if not for the repeated large volume expansion and shrinkage that cause SEI particles to shed.
but yolk-shell particles feature a void between the two equivalent to where the white of an egg would be.
The aluminum particles they used, which are about 50 nanometers in diameter, naturally have oxidized an layer of alumina (Al2o3).
a better conductor of electrons and lithium ions when it is very thin. Aluminum powders were placed in sulfuric acid saturated with titanium oxysulfate.
if the particles stay in the acid for a few more hours, the aluminum core continuously shrinks to become a 30-nm-across olk,
The particles are treated then to get the final aluminum-titania (ATO) yolk-shell particles. After being tested through 500 charging-discharging cycles,
and electrons to get in and out. The result is an electrode that gives more than three times the capacity of graphite (1. 2 Ah/g) at a normal charging rate
indicating ATO is quite close to being ready for real applications. hese yolk-shell particles show very impressive performance in lab-scale testing,
The principle was tested at the HZDR on a typical laboratory laser as well as on the free-electron laser FELBE.
If particles can be organized into sufficiently large crystals, their structure can be determined through crystallography, which involves shooting x-rays through a crystal.
As an alternative and complementary technique, structural biologists often gather diffraction patterns from particles in solution. However, in these so called small-and wide-angle x-ray scattering (SAXS/WAXS) experiments
particles can rotate during imaging, which results in a loss of information and often leads to a poor reconstruction of the unknown structure.
the goal is to provide the scientific community with a powerful new tool to determine the structure and dynamics of nano-sized particles in a routine,
but this is an important breakthrough. he researchers emphasize that FXS data may also be collected using an ultrabright synchrotron light source from particles cryogenically frozen in place.
#Researchers Evaluate Particle Retention and Stability on Nanomembrane Sheets In a new study, Cornell researchers examined these special nylon sheets replete with applied nanoscale iron oxide particles to see
if the particles wash loose. The particles work like magnets to capture bacteria and viruses,
and to extract chemicals or dye molecules out of water. Membranes with these particles attached could be used in devices to detect water contamination
or in filters to remove chemicals or dyes from industrial waste. However, to be effective and safe,
the particles need to stay on the membrane. The study evaluated the nanoparticle treatment uniformity and particle retention of the nylon membranes as they were processed
(or washed) in solutions of varying ph levels. t critical to evaluate particle retention and stability on fibers to reduce human health
and environmental concerns, said Nidia Trejo, a Cornell doctoral student in the field of fiber science. Trejo, who with Margaret Frey, professor of fiber science, authored the study, comparative study on electrosprayed, layer-by-layer,
and chemically grafted nanomembranes loaded with iron oxide nanoparticles, in the Journal of Applied Polymer Science, July 14.
layer-by-layer assembly, where particles are coated on the fiber electrostatically; or chemical bonding. or the membrane, it important to evaluate particle retention and stability,
Trejo explained. ou would want the nanoparticles to stay on the Nylon 6 membranes so the material can have function throughout the life use.
you wouldn want the particles themselves to become pollutants if are they releasing from the membranes
"The study was supported also by X-ray experiments at SSRL and at Argonne National Laboratory's Advanced Photon Source."
and gleaning information from every photon emitted from a sample's fluorescent labels, labels are preserved
Traditional scanning electron and atomic force microscopy techniques can damage a sample. The University of Colorado approach promises quantitative full-field imaging with as much as a 20x improvement in spatial resolution,
Notable demonstrations aside, current X-ray, electron and optical microscopies are simply too cumbersome and slow to routinely image functioning systems in real space and time, severely limiting progress.
making the particle unstructured or amorphous. Researchers from Harvard John A. Paulson School of engineering and Applied science (SEAS) have developed a new system that can produce stable, amorphous nanoparticles in large quantities that dissolve quickly.
structure, and size of particles, enabling the formation of new materials, said Amstad. It allows us to see
which the particles are suspended; these assemblies can be used, among other things, for reversibly writing information.
It is this reaction that causes the particles to aggregate in the dark and disperse in the light.
For one, the particles do not seem to degrade over time a problem that plagues the coated nanoparticles. e ran one hundred cycles of writing
"We're good at generating electrons from light efficiently, but chemical synthesis always limited our systems in the past.
which are extremely small melanin particles, Zharov said. any years ago we discovered that laser-induced high local temperature can evaporate liquid surrounding light-absorbing nanoparticles
which analyzes particles for the real-time control of CTC release, and then eradicate the CTCS by well-timed therapy including nanobubble-based treatment.
and single-particle averaging (SPA)--to resolve individual components of SPB duplication in living yeast cells.
which uses a beam of electrons to achieve molecular and even atomic resolutions, has been the go-to technique for studying SPBS,
The other, single-particle averaging (SPA), brings tiny objects and their locations into sharper focus by averaging many images into one"typical"picture.
The study, published in the Journal of Dentistry, shows how sub-micron silica particles can be prepared to deliver important compounds into damaged teeth through tubules in the dentine.
The tiny particles can be bound to compounds ranging from calcium tooth building materials to antimicrobials that prevent infection.
with the particles acting like seeds for further growth that would close the tubules. Previous attempts have used compounds of calcium fluoride, combinations of carbonate-hydroxypatite nanocrystals and bioactive glass,
However, the Birmingham team turned to sub-micron silica particles that had been prepared with a surface coating to reduce the chance of aggregation.
When observed using high definition SEM (Scanning Electron Microsopy the researchers saw promising signs that suggested that the aggregation obstacle had been overcome.
"These silica particles are available in a range of sizes, from nanometre to sub-micron,
""We tested a number of different options to see which would allow for the highest level particle penetration into the tubules,
and then see how effective the particles are blocking the communication with the inside of the tooth.
which a beam of electrons smaller than the size of a hydrogen atom is scanned over a sample
and measures how many electrons interact with the atoms at each scan position. The method reveals the atomic structure of materials
because different arrangements of atoms cause electrons to interact in different ways. However, scanning transmission electron microscopes only produce two-dimensional images.
The downside of this technique is repeated that the electron beam radiation can progressively damage the sample.
thanks to the electron beam energy being kept below the radiation damage threshold of tungsten. Miao and his team showed that the atoms in the tip of the tungsten sample were arranged in nine layers, the sixth
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