Graphene is a two-dimensional sheet of carbon atoms, just one atom thick. Its flexibility, optical transparency and electrical conductivity make it suitable for a wide range of applications,
"Hasan's method, developed at the University's Nanoscience Centre, works by suspending tiny particles of graphene in a'carrier'solvent mixture,
Light goes infinitely fast with new on-chip material Electrons are so 20th century. In the 21st century, photonic devices,
or waveguide to emit photons which are always in phase with one another, "said Philip Munoz,
and infinitely long, enabling even distant particles to be entangled.""""This on-chip metamaterial opens the door to exploring the physics of zero index
In the metal state, electrons move freely, while in the insulator state, electrons cannot flow.
This on/off transition, inherent to vanadium dioxide, is also the basis of computer logic and memory.
This work will be reported at the IEEE International Electron Device Meeting, the leading forum for reporting technological breakthroughs in the semiconductor and electronic device industry, in December."
"explains Gabriele Giachin, first author of the study and former SISSA Phd student (today at the European Synchrotron radiation Facility, ESRF, in Grenoble, France)."
#Umbrella-shaped diamond nanostructures make efficient photon collectors Standard umbrellas come out when the sky turns dark,
a team of researchers in Japan has discovered that"umbrella-shaped"diamond nanostructures with metal mirrors on the bottom are more efficient photon collectors than their diamond nanostructure"cousins"of other shapes.
"Umbrella-shaped diamond provides significantly better photon collection efficiency than bulk diamond or its pillar-shaped diamond counterpart,
The significance of the team's discovery is that they've shown that the brighter fluorescence intensity of umbrella-shaped diamond nanostructures can be achieved by improving the photon collection efficiency of the nitrogen vacancy centers,
These nitrogen vacancy centers possess unique properties such as optical initialization and detection of its spin states, stable and strong fluorescence even from a single center
and long spin coherence time at room temperature. These properties make nitrogen vacancy centers in diamonds candidates for next-generation spin-based quantum devices such as magnetometers, quantum computers,
Brighter fluorescence intensity is an essential aspect of improving the photon collection efficiency from nitrogen vacancy centers.
Due to the high refractive index (2. 4) of diamond, the photon collection efficiency from the nitrogen vacancy centers in bulk diamond is low."
"Our goal now is to improve the nanostructures'photon collection efficiency, "she said.""We also plan to demonstrate quantum sensors--in particular,
Cobalt atoms on graphene a powerful combo Graphene doped with nitrogen and augmented with cobalt atoms has proven to be an effective, durable catalyst for the production of hydrogen from water, according to scientists at Rice university.
The Rice lab of chemist James Tour and colleagues at the Chinese Academy of Sciences, the University of Texas at San antonio and the University of Houston have reported the development of a robust,
Catalysts can split water into its constituent hydrogen and oxygen atoms, a process required for fuel cells.
"What's unique about this paper is that we show not the use of metal particles, not the use of metal nanoparticles,
but the use of atoms,"Tour said.""The particles doing this chemistry are as small as you can possibly get."
"Even particles on the nanoscale work only at the surface, he said.""There are so many atoms inside the nanoparticle that never do anything.
But in our process the atoms driving catalysis have no metal atoms next to them.
We're getting away with very little cobalt to make a catalyst that nearly matches the best platinum catalysts."
"In comparison tests, he said the new material nearly matched platinum's efficiency to begin reacting at a low onset voltage,
Tour said single-atom catalysts have been realized in liquids, but rarely on a surface.""This way we can build electrodes out of it,
"The researchers discovered that heat-treating graphene oxide and small amounts of cobalt salts in a gaseous environment forced individual cobalt atoms to bind to the material.
Electron microscope images showed cobalt atoms widely dispersed throughout the samples. They tested nitrogen-doped graphene on its own and found it lacked the ability to kick the catalytic process into gear.
"Atom-thick graphene is the ideal substrate, Tour said, because of its high surface area, stability in harsh operating conditions and high conductivity.
#Single atom alloy platinum-copper catalysts cut costs, boost green technology A new generation of platinum-copper catalysts that require very low concentrations of platinum in the form of individual atoms to cleanly
isolated platinum atoms in much less costly copper surfaces can create a highly effective and cost-efficient catalyst for the selective hydrogenation of 1, 3 butadiene,
"We were excited to find that the platinum metal dissolved in copper, just like sugar in hot coffee, all the way down to single atoms.
We call such materials single atom alloys, "said Sykes. The Tufts chemists used a specialized low temperature scanning tunneling microscope to visualize the single platinum atoms and their interaction with hydrogen."
"We found that even at temperatures as low as minus 300 degrees F these platinum atoms were capable of splitting hydrogen molecules into atoms,
indicating that the platinum atoms would be very good at activating hydrogen for a chemical reaction,
"Sykes said. With that knowledge, Sykes and his fellow chemists turned to long-time Tufts collaborator Maria Flytzani-Stephanopoulos, Ph d.,the Robert and Marcy Haber Endowed Professor in Energy Sustainability at the School of engineering,
such as platinum-copper single atom alloy nanoparticles supported on an alumina substrate, and then tested them under industrial pressure and temperatures."
because clusters of platinum atoms have compared inferior selectivity with individual atoms.""In this case, less is said more
and manipulate atoms and molecules, and I wanted to use its unique capabilities to gain insight into industrially important chemical reactions.
In the early 2000s, Maria's group had pioneered the single-atom approach for metals anchored on oxide supports as the exclusive active sites for the water-gas shift reaction to upgrade hydrogen streams for fuel cell use.
Together we embarked on a new direction involving single atom alloys as catalysts for selective hydrogenation reactions.
"Sykes and Flytzani-Stephanopoulos have used this approach to design a variety of single atom alloy catalysts that have,
and properties of single atom alloy surfaces and then applied this knowledge to develop a working catalyst.
Armed with this knowledge, we are now ready to compare the stability of these single atom alloy catalysts to single atom catalysts supported on various oxide or carbon surfaces.
and the University of New mexico School of medicine has identified a small molecule that treats animal models of aged macular degeneration (AMD)
show that this molecule, named Vasotide in this paper, can be delivered in the form of eye drops,
which require monthly injections of large molecules directly into the eyeball.""Angiogenesis, the abnormal overgrowth of blood vessels, underlies many severe diseases,
"Vasotide is the only external agent that uniquely blocks VEGF from binding to two different endothelial receptor molecules--VEGF receptor-1
Androgens are important signaling molecules, which play an essential role in men's health by driving the development, repair and regeneration of the prostate and other tissues.
"Our current study suggests one mechanism at play is that a unique and rare type of tau has the properties we were looking for-it is released from neurons,
"Previous research has shown that tau tangles first appear in a structure located deep within the brain called the entorhinal cortex,
Several 2013 studies from Hyman's group and others showed the movement of a mutant form of tau between brain structures and resultant neurodegeneration in a mouse model.
only 1 percent of the tau in those samples was taken up by the neurons. The tau proteins that were taken up were high molecular weight-meaning that a number of smaller proteins are bound together into a larger molecule-soluble,
and studded with a large number of phosphate molecules, a known characteristic of the tau in Alzheimer's-associated tangles.
Similar results were seen in experiments using brain samples from Alzheimer's patients both in cultured neurons and in living mice.
The process by which this version of tau passes between neurons was illustrated using a microfluidic device developed at the MGH Biomems Resource Center.
The team found that applying this rare form of tau from the brains of the mouse model to neurons in the first chamber resulted in the protein's being taken up by those neurons and
A few days later, tau was detected at the end of axons extending from the second to the third chamber,
Removal of tau from the first chamber did not cause it to disappear from the second chamber,
Additional experiments with tau from the brains of Alzheimer's patients confirmed that the high-molecular-weight
and uptake of this form of tau is an important step in the spread of disease from one brain region to another,
"The electrons in topological insulators have unique quantum properties that many scientists believe will be useful for developing spin-based electronics and quantum computers.
In Science Advances, the researchers report the discovery of an optical effect that allows them to"tune"the energy of electrons in these materials using light,
which arises from quantum interference between the different simultaneous paths that electrons can take through a material
Germanium is a semiconductor and this method provides a straightforward way to make semiconducting nanoscale circuits from graphene, a form of carbon only one atom thick.
The method was discovered by UW scientists and confirmed in tests at Argonne.""Some researchers have wanted to make transistors out of carbon nanotubes
"UW researchers used chemical vapor deposition to grow graphene nanoribbons on germanium crystals. This technique flows a mixture of methane, hydrogen and argon gases into a tube furnace.
At high temperatures, methane decomposes into carbon atoms that settle onto the germanium's surface to form a uniform graphene sheet.
when graphene grows on germanium, it naturally forms nanoribbons with these very smooth, armchair edges,"said Michael Arnold, an associate professor of materials science and engineering at UW-Madison."
"Graphene, a one-atom-thick, two-dimensional sheet of carbon atoms, is known for moving electrons at lightning speed across its surface without interference.
and stop electrons at will via bandgaps, as they do in computer chips. As a semimetal, graphene naturally has no bandgaps,
a technique using electrons (instead of light or the eyes) to see the characteristics of a sample,
researchers confirmed the presence of graphene nanoribbons growing on the germanium. Data gathered from the electron signatures allowed the researchers to create images of the material's dimensions and orientation.
In addition, they were able to determine its band structure and extent to which electrons scattered throughout the material."
"We're looking at fundamental physical properties to verify that it is, in fact, graphene and it shows some characteristic electronic properties,
"What's even more interesting is that these nanoribbons can be made to grow in certain directions on one side of the germanium crystal,
"For use in electronic devices, the semiconductor industry is interested primarily in three faces of a germanium crystal.
where single atoms connect to each other in a diamond-like grid structure, each face of a crystal (1, 1,
0). Previous research shows that graphene sheets can grow on germanium crystal faces (1, 1, 1) and (1, 1,
if there is any unique interaction between the germanium and graphene that may play a role e
which does not damage the delicate biological molecules or living cells that were bioprinted. As a next step, the group is working towards incorporating real heart cells into these 3-D printed tissue structures,
Spritam (levetiracetam) is not actually a new molecule. The innovation here is not that Aprecia Pharmaceuticals has found a new treatment for seizure disorders,
If the photons merely pass through, or get reflected, they won deposit enough energy for cutting.
The release stories for this laser mention that the infrared wavelengths used here are safer for the eye than either visible or UV radiation.
When electron-laden lithium ion diffuse across this gap and offload their electrons at the other side,
This removes some lithium ions from the system, thus reducing the total available charge in the battery.
and removing any of the lithium ions themselves. The delay in removing the aluminum from the chemical bath did not result in the shell around the aluminum core
the researchers did have needed the insight to put the particles through their experimental paces, rather than simply throwing them out.
have been predicted to kill lithium ion for many years running, at this point Ie made the prediction myself, more than once.
#Particle collider creates rimordial gooof the early universe A quark-gluon plasma is the original state of the universe.
This means that there was nothing larger or more organized than single subatomic particles the constituents of relatively enormous things like protons.
That why it so surprising that an American particle collider called the Relativistic Heavy ion Collider (RHIC) was able to create it with very little actual mass.
blasting apart matter so violently that even hadrons can form takes a lot of input energy. In general, it been assumed that any particle collider looking to create a sample of quark-gluon plasma would have to smash together very heavy atomic nuclei.
The Large hadron collider, and the RHIC itself, have created both quark-gluon plasmas in the past, by making incredibly violent collisions between heavy atoms like lead or gold.
What this particular RHIC experiment did was to create a quark-gluon plasma by colliding a the nucleus of a helium-3 atom with an atom of gold
which was thought not previously to be possible. The pockets of plasma born of these collisions are much smaller than those created by heavier atoms,
but they hung around long enough for scientists to measure their properties. The experiment proved that they are indeed in a state called a erfect fluid, in
which matter has no internal friction at all, and conducts no heat. This is mostly a tool for physicists in their thought experiments;
in the vast majority of real-world cases, a perfect fluid is totally impossible. But the Big bang is thought to have put all the matter in the universe into this state, all that once.
A helium-3 nucleus is made of two protons (thus, making it helium) and a neutron, making it one neutron lighter than the most common helium isotope On earth.
This three-particle nucleus was chosen because it is one particle heavier than a two-particle deuterium atom,
which the Large hadron collider and the RHIC have smashed previously into gold in search of similar results.
These helium collisions were conducted in 2014 and have just now been published; the team conducted similar tests with single protons in 2015.
The results of those collisions have yet to be published. The ability to create an ever wider array of samples of quark-gluon plasma will be important,
not because the plasma itself will ever be long-lived enough to be useful, but because the data gathered as it winks in
and out of existence can offer a window into the very earliest events in the history of the universe.
So, as interesting as it is that smaller collisions can create smaller, more localized droplets of quark-gluon plasma
the larger, stronger signals from larger impacts may be the primary interest for research
#The first satellite powered entirely by ion engines is online Getting a satellite into orbit is only the first step in making it a useful piece of equipment.
It also needs to arrive in the correct orbit and stay there, known as station-keeping.
Now Boeing has announced the first all-electric ion propulsion satellite is fully operational. The satellite in question doesn have a snappy name it a communications satellite called ABS-3a 702sp.
Ion thrusters make a lot of sense in this scenario. Ion engines operate on the same basic principles of physics that chemical thrusters do expel mass from a nozzle to push a craft in the opposite direction.
which is currently studying the dwarf planet Ceres. Ion thrusters are considerably more efficient than conventional rocket motors.
In this case, Boeing claims the Xenon Ion Propulsion system (XIPS) designs used for ABS-3a is ten times more efficient than liquid fueled rockets.
Ion thrusters are also considerably lighter than chemical engines making launches cheaper. The drawback is the very low thrust of an ion engine.
Upon delivery to orbit, ABS-3a used its ion thrusters to reach a geosynchronous orbit at 3 degrees west longitude.
Sensation coming from a bionic source does not have to be speed-limited by the diffusion of ions in solution
#New quantum dot could make quantum communications possible A new form of quantum dot has been developed by an international team of researchers that can produce identical photons at will,
Many upcoming quantum technologies will require a source of multiple lone photons with identical properties,
The reason we need identical photons for quantum communication comes back to the non-quantum idea of key distribution.
Quantum key distribution uses the ability of quantum physics to provide evidence of surveillance. Rather than making it impossible to intercept the key,
In particular, the wavelength of photons changes as they move down an optical fiber not good since creating photon with precise attributes is the whole source of quantum security.
So, unless youe less than one quantum dot range away from the person you want to talk to,
These quantum dots basically achieve perfect single-photon emission by super-cooling the quantum dots so the emitting atoms do not fluctuate.
reading each photon as it absorbed and reemitted. Potential attackers could install optical splitters so they get
Short of telepathy, there will never be perfect communication security not even quantum physics can change that y
The fact that chlorophyll absorption spectrum makes things surprisingly green reflects the compromises inherent in being able to capture every photon possible
Terahertz (THZ) radiation. Oscillating at around 1 trillion times per second, THZ waves were utilized previously for the wireless data transmission world record,
some of the radiation leaks out. The angle the radiation leaks out is dependent on its frequency,
hence 10 different frequencies will radiate at 10 different angles (demultiplexing) and by reversing the process the device can multiplex.
whether the interaction of THZ radiation with biological organisms is safe. A theoretical study published by MIT in 2009 suggested that THZ waves may interfere with DNA via nonlinear instabilities,
however the process was extremely unlikely and required long exposure to the radiation. Until sufficient experimental biological data is gathered,
however the consensus thus far because THZ radiation is non-ionizing is that damage to humans is extremely unlikely i
The discovery comes thanks to the Mars Reconnaissance Orbiter and its imaging spectrometer, which enabled researchers to find telltale signs of hydrated minerals on streaked-looking slopes.
and later paired those images with mineral maps from the spacecraft Compact Reconnaissance Imaging Spectrometer for Mars (CRISM).
the treatments that work against multiple types of cancer like chemotherapy and radiation are often so harsh and hazardous that doctors hesitate to prescribe them.
which allows for much higher energy-efficiency. While Gan transistors have several benefits over silicon, safety drawbacks and expensive manufacturing methods have kept largely them off the market.
Fortunately, researchers at Stanford university are building an aluminum-ion battery prototype that speeds up the charging times.
And the aluminum-ion battery could eventually replace many of the lithium-ion and alkaline batteries used in many smartphones today. e have developed a rechargeable aluminum battery that may replace existing storage devices, such as alkaline batteries,
and lithium-ion batteries, which occasionally burst into flames, said Stanford university chemistry professor Hongjie Dai, the lead researcher of the project,
An aluminum-ion battery generally consists of two electrodes, one negatively charged anode made of aluminum and a positively charged cathode.
Researchers have been interested in developing a commercially viable aluminum-ion battery for decades, but efforts have been largely unsuccessful.
Lithium-ion batteries are also potentially a fire hazard. This is why United airlines and Delta air lines banned bulk lithium battery shipments on passenger planes.
which makes it much safer than lithium-ion batteries. Lithium-ion batteries also takes hours to charge,
but the aluminum-ion prototype at Stanford takes only one minute. The aluminum batteries developed at Stanford university are more durable than other batteries.
For example, aluminum batteries developed at other laboratories died after just 100 charge-discharge cycles. The aluminum battery developed at Stanford was able to withstand more than 7, 500 cycles without any capacity loss.
Lithium-ion batteries generally last about 1, 000 cycles. The aluminum battery is also flexible so it can be used in electronic devices that can fold and bend.
Aluminum-ion technology is an environmentally friendly alternative to disposable alkaline batteries too. The rechargeable aluminum battery created by Stanford researchers generates about two volts of electricity,
Before Stanford aluminum-ion battery is mass produced, the research team will have to improve the cathode material to increase the voltage and energy density.
The findings in the research will be published in a paper titled n ultrafast rechargeable aluminum-ion batteryfor the April 6th advance online edition of Nature. com. The other co-lead authors of the study
Here is a video about the development of aluminum-ion battery at Stanfor a
#That Self-driving car In Your Future Might Make You Sick Remember back when virtual reality was being touted as The next Big Thing the first time around?
. While Oncor Electric is still sending electrons to its 7. 5 million customers throughout Texas using high-voltage transmission lines,
The electrons are sent then by microgrids to keep those operations running. The concept is catching on nationally,
The Michigan company Xalt Energy markets a lithium-ion battery that it says can cycle 4, 000 to 8, 000 times.
Some lithium-ion batteries used to back up data servers are designed to cycle up to 10,000 times.
pellets forming a conductive ion trail, sacrificial conductors, projectiles trailing electrical wires or magnetic induction If the first medium is,
The photoanode uses sunlight to oxidize water molecules, generating protons and electrons as well as oxygen gas.
The photocathode recombines the protons and electrons to form hydrogen gas. NO EXPLOSIONS A key part of the design is the plastic membrane,
which keeps the oxygen and hydrogen gases separate. If the two gases are allowed to mix
and electrons to pass through. The new system uses such a 62.5-nanometer-thick Tio2 layer to effectively prevent corrosion
This catalyst is among the most active known catalysts for splitting water molecules into oxygen, protons,
and electrons and is a key to the device high efficiency. The photoanode was grown onto a photocathode
says Schwab. e all know quantum mechanics explains precisely why electrons behave weirdly. Here wee applying quantum physics to something that is relatively big,
a device that you can see under an optical microscope, and wee seeing the quantum effects in a trillion atoms instead of just one.
Because this noisy quantum motion is always present and cannot be removed, it places a fundamental limit on how precisely one can measure the position of an object.
Schwab explains. e showed that we can actually make the fluctuations of one of the variables smallert the expense of making the quantum fluctuations of the other variable larger. hat is called
ripples in the fabric of space-time. ee been thinking a lot about using these methods to detect gravitational waves from pulsarsncredibly dense stars that are the mass of our sun compressed into a 10 km radius and spin at 10 to 100 times a second,
In order to do that, the current device would have to be scaled up. ur work aims to detect quantum mechanics at bigger and bigger scales, and one day
laser cutting, and particle acceleration. ou generally would need a large optical setup, consisting of multiple components,
The team is currently working with industrial partners to create metasurfaces for use in commercial devices such as miniature cameras and spectrometers,
Bonventre holds patents on kidney injury molecule-1 which have been assigned to Partners Healthcare. The other researchers declare no competing interests t
This phase, characterized by an unusual ordering of electrons, offers possibilities for new electronic device functionalities and could hold the solution to a longstanding mystery in condensed matter physics having to do with high-temperature superconductivityhe ability
first consider a crystal with electrons moving around throughout its interior. Under certain conditions, it can be energetically favorable for these electrical charges to pile up in a regular,
In addition to charge, electrons also have a degree of freedom known as spin. When spins line up parallel to each other (in a crystal, for example
they form a ferromagnethe type of magnet you might use on your refrigerator and that is used in the strip on your credit card.
Because spin has both a magnitude and a direction, a spin-ordered phase is described by a vector.
Over the last several decades, physicists have developed sophisticated techniques to look for both of these types of phases.
But what if the electrons in a material are ordered not in one of those ways?
And like the cuprates, iridates are electrically insulating antiferromagnets that become increasingly metallic as electrons are added to
where an additional amount of energy is required to strip electrons out of the material. For decades, scientists have debated the origin of the pseudogap
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