"Although surface atoms represent a minuscule fraction of the total number of atoms in a material, these atoms drive a large portion of the material's chemical interactions with its environment."
and improve material performance it is vital to know how the atoms are arranged at surfaces. While there are now many good methods for obtaining this information for rather flat surfaces,
""The beauty of this technique is that we can image surface atoms and bulk atoms simultaneously,"says co-author Zhu, a scientist at Brookhaven National Laboratory."
"Currently none of any existing methods can achieve this.""Scanning electron microscopy (SEM) is an excellent technique for studying surfaces
and bulk atoms simultaneously, retaining much of the surface sensitivity of traditional SEM through secondary electrons.
and causing atoms in the material to emit energy in the form of electrons rather than photons.
and analyzed in detail a series of HRSEM images of a particular arrangement of atoms at the surface of strontium titanate.
2015cellulose from wood can be printed in 3-D June 17th, 2015solar cells in the roof and nanotechnology in the walls June 16th, 2015buckle up for fast ionic conduction June 16th,
Using electron microscopy and ion beam milling, Yu group discovered that the ants are covered on the top
"This collaborative team was one of two to first demonstrate polaritons in single-atom layers of carbon called graphene.
Columbia engineers and colleagues create bright, visible light emission from one-atom thick carbon June 15th, 2015research partnerships Lancaster University revolutionary quantum technology research receives funding boost June 22nd, 2015fabricating inexpensive, high-temp SQUIDS for future electronic devices June 22nd,
"At just one atom thick, graphene is the thinnest substance capable of conducting electricity. It is very flexible
including single atoms and larger structures, during an active reaction at room temperature,"said study coauthor and Brookhaven Lab scientist Eric Stach."
while ions can still migrate from the anode to the cathode. The electrolyte plays a key role.
It must permit only the appropriate ions to pass between the anode and cathode. If free electrons or other substances could travel through the electrolyte,
Advancements in the electrolyte system of PEMFCTHE commercial development of a special electrolyte (single ion conducting polymer electrolyte) changed the field of electrochemical devices in a significant way.
Electrochemists have spent many years in a continuing search for newer, more highly conducting (ions and not electrons) and a more electrochemically stable electrolyte system.
With the development of a single ion (for example only hydrogen ions in PEMFC) conducting polymer, electrochemists have the ability to choose from a variety of polymers with both high conductivity for a given ion of interest (off course hydrogen ions
New technique combines electron microscopy and synchrotron X-rays to track chemical reactions under real operating conditions June 29th, 2015buckle up for fast ionic conduction June 16th, 2015a protective shield for sensitive catalysts:
which some of the metallic ions are placed. The size and shape of the pores are very effective in the selective sorption of the ions.
Based on the positive results the nanosorbent can be used in various industries such as foodstuff and petroleum to detect
News and information Samsung's New Graphene technology Will Double Life Of Your Lithium-Ion Battery July 1st,
2015announcements Samsung's New Graphene technology Will Double Life Of Your Lithium-Ion Battery July 1st, 2015researchers from the UCA, key players in a pioneering study that may explain the origin of several digestive diseases June 30th,
2015interviews/Book reviews/Essays/Reports/Podcasts/Journals/White papers Samsung's New Graphene technology Will Double Life Of Your Lithium-Ion Battery July 1st,
highly symmetrical planes of oxygen atoms (somewhat like a densely packed box of marbles) where different metallic elements are lodged in the spaces between them.
The embedded metal ions in the Ni1-xcuxcr2o4 spinel system cause a distortion of the crystal structure.
or copper atoms sit at what are referred to as tetragonal sites of the crystal structure. Due to their different configurations of electrons, these tetrahedra become elongated along the crystallographic c-axis for nickel,
since the kinetic energy of the atoms still suppresses the Jahn-Teller effect and magnetic ordering cannot become established.
"Atoms are not just spheres. They do crazy things, especially when they are in a geometrical system like a crystal,
instead depends upon the uncanny ability of gold atoms to trap silicon-carrying electrons to selectively prevent the etching.
the researchers found that even a sparse cover of gold atoms over the silicon matrix would prevent etching from occurring in their proximity.
which includes oxygen atoms. It has high oxidizing power with high reactivity, and is reported to be effective to process pollutants in the air.
and are converted to innocuous oxygen (O2) before being discharged into the surrounding. 2. Oxygen radical Oxygen radical is an oxygen atom in the atomic state prior to being combined into a molecule. 3. Total volatile organic compounds (TVOC
because they have consisted only of a few layers of thermal conductive atoms. When you try to add more layers of graphene,
In this study, researchers first pattern nanostructures on the graphene surface by bombarding it with electron beams and etching it with oxygen ions.
this process can also reveal the nature of the bonds connecting the atoms that make up the molecule.
the bonds between atoms are stretched or compressed to accommodate the bending, but in nanoscale materials there is time for the atoms to also move,
or diffuse, from the compressed area to the stretched area in the material. If you think of the bent nanowire as an arch,
the atoms are moving from the inside of the arch to the outside. When the tension in the bent wire is released,
the atoms that simply moved closer or further apart snap back immediately; this is what we call elasticity.
But the atoms that moved out of position altogether take time to return to their original sites.
because it is much easier for atoms to move through nanoscale materials than through bulk materials.
And the atoms don't have to travel as far. In addition nanowires can be bent much further than thicker wires without becoming permanently deformed or breaking."
Here, we show that lignin nanoparticles infused with silver ions and coated with a cationic polyelectrolyte layer form a biodegradable and green alternative to silver nanoparticles.
together with silver ions, can kill a broad spectrum of bacteria, including Escherichia coli, Pseudomonas aeruginosa and quaternary-amine-resistant Ralstonia sp.
Ion depletion studies have shown that the bioactivity of these nanoparticles is limited time because of the desorption of silver ions.
NC State engineer Orlin Velev and colleagues show that silver-ion infused lignin nanoparticles, which are coated with a charged polymer layer that helps them adhere to the target microbes,
As it turns out, a group of atoms essential to the drug molecule's effectiveness,
#Researchers Build a Transistor from a Molecule and A few Atoms A team of physicists from the Paul-Drude-Institut für Festkörperelektronik (PDI) and the Freie Universität Berlin (FUB), Germany, the NTT
and the U s. Naval Research Laboratory (NRL), United states, has used a scanning tunneling microscope to create a minute transistor consisting of a single molecule and a small number of atoms.
The team used a highly stable scanning tunneling microscope (STM) to create a transistor consisting of a single organic molecule and positively charged metal atoms
to assemble electrical gates from the+1 charged atoms with atomic precision and, then, to place the molecule at various desired positions close to the gates.
In our case, the charged atoms nearby provide the electrostatic gate potential that regulates the electron flow
But there is a substantial difference between a conventional semiconductor quantum dot comprising typically hundreds or thousands of atoms and the present case of a surface-bound molecule:
-Legislation/Regulation/Funding/Policy Researchers Build a Transistor from a Molecule and A few Atoms July 14th, 2015world first:
The one-atom-thick carbon sheets could revolutionize the way electronic devices are manufactured and lead to faster transistors, cheaper solar cells, new types of sensors and more efficient bioelectric sensory devices.
which ions are accelerated under an electrical field and smashed into a semiconductor. The impacting ions change the physical, chemical or electrical properties of the semiconductor.
In a paper published this week in the journal Applied Physics Letters, from AIP Publishing,
Graphene's unique optical, mechanical and electrical properties have lead to the one-atom-thick form of carbon being heralded as the next generation material for faster, smaller, cheaper and less power-hungry electronics."
In the process, carbon ions were accelerated under an electrical field and bombarded onto a layered surface made of nickel, silicon dioxide and silicon at the temperature of 500 degrees Celsius.
in addition to other parameters such as density difference in electrical charges and type and density of surface atoms,
and it cannot be applied for the inspection of foods that have lactic acid bacteria because X-ray radiation causes ionization of such foods.
The new material is composed of a silica sol-gel thin film containing polar groups linked to the silicon atoms and a nanoscale self-assembled monolayer of an octylphosphonic acid,
#Scientists print low cost radio frequency antenna with graphene ink (Nanowerk News) Scientists have moved graphene--the incredibly strong and conductive single-atom-thick sheet of carbon--a significant step along the path
The new findings using a layer of one-atom-thick graphene deposited on top of a similar 2-D layer of a material called hexagonal boron nitride (hbn) are published in the journal Nano Letters("Tunable Lightatter
Although the two materials are structurally similar both composed of hexagonal arrays of atoms that form two-dimensional sheets they each interact with light quite differently.
which ions and electrons must rapidly move. Researchers have built arrays of nanobatteries inside billions of ordered,
identical nanopores in an alumina template to determine how well ions and electrons can do their job in such ultrasmall environments.
The nanobatteries were fabricated by atomic layer deposition to make oxide nanotubes (for ion storage) inside metal nanotubes for electron transport, all inside each end of the nanopores.
and well-controlled fabrication of nanotubular electrodes to accommodate ion motion in and out and close contact between the thin nested tubes to ensure fast transport for both ions and electrons.
Complete nanobatteries are formed in each nanopore of a dense nanopore array (2 billion per cm2),
while their ion insertion processes occur very fast, much like what happens at the surface of a double-layer capacitor.
and discharge) and for extended cycling, demonstrating that precise nanostructures can be constructed to assess the fundamentals of ion
#Large-scale simulations of atom dynamics An international research team has developed a highly efficient novel method for simulating the dynamics of very large systems potentially containing millions of atoms,
and gaining a previously unattainable understanding of processes such as electron, water or ion transport or chemical reactions.
to only a few hundred atoms. For the first time, this new method provides the means of performing atomic and electronic structure simulations on much larger systems,
Matter is composed of atoms, and its physical characteristics are determined by the complex interactions between atoms and electrons.
Theoreticians use quantum mechanics to calculate the forces between atoms, and the behaviour of electrons in materials.
Specifically, first-principles simulations are based on quantum mechanics, and are a powerful technique widely used to uncover diverse properties of matter and materials at the atomic scale.
where the time required for the calculations increases linearly with the number of atoms, to perform first-principles dynamical simulations of systems comprising more than 30,000 atoms,
100 times larger than is usual with conventional methods. The technique has further been used to calculate properties of over 2 million atoms.
This new method will be an invaluable tool for those using predictive computational modelling and, as most simulations are stuck below 1,
000 atoms, it will open the doors to studying completely new areas of physics s
It also potentially allows for the generation of intense femotosecond electron pulses that could increase resolution for time-resolved electron microscopes that follow the motion of individual atoms
The researchers have studied the sensitivity of thermometers created with a handful of atoms, small enough to be capable of showing typical quantum-style behaviours.
This produces a plasma consisting of carbon ions, which is deposited as a coating on the workpiece in the vacuum.
An intense Gaussian-shaped x-ray pulse (transparent blue shape) has passed just through a cluster of Argon atoms (pink spheres.
But first, many atoms and molecules will have to meet with a sci-fi appropriate demise. And the ability to capture
when x-ray photons collide with the electrons of a target samplea specific atom or enzyme molecule, for instanceand scatter.
a one-atom thick form of carbon. Tunneling electrons from a scanning tunneling microscope tip excites phonons in graphene.
the forces that bond the atoms together cause the atoms to vibrate and spread the energy throughout the material,
and measure how much energy the electrons have transferred to the vibrating atoms. But it's difficult.
"Although surface atoms represent a minuscule fraction of the total number of atoms in a material, these atoms drive a large portion of the material's chemical interactions with its environment."
and provides information on both surface and bulk atoms simultaneously. Image: Jim Ciston, Berkeley Lab) Ciston is the lead
and improve material performance it is vital to know how the atoms are arranged at surfaces. While there are now many good methods for obtaining this information for rather flat surfaces,
""The beauty of this technique is that we can image surface atoms and bulk atoms simultaneously,"says co-author Zhu, a scientist at Brookhaven National Laboratory."
"Currently none of any existing methods can achieve this.""Scanning electron microscopy (SEM) is an excellent technique for studying surfaces
and bulk atoms simultaneously, retaining much of the surface sensitivity of traditional SEM through secondary electrons.
and causing atoms in the material to emit energy in the form of electrons rather than photons.
and analyzed in detail a series of HRSEM images of a particular arrangement of atoms at the surface of strontium titanate.
"Why It Matterslithium-ion batteries have many uses besides powering cell phones and laptops. Developing safer, more powerful cells with longer life is a worldwide challenge,
In an engineering first, Cui and his colleagues used lithium-ion battery technology to create one low-cost catalyst that is capable of driving the entire water-splitting reaction.'
'Our group has pioneered the idea of using lithium-ion batteries to search for catalysts, 'Cui said.'
The idea is to use lithium ions to chemically break the metal oxide catalyst into smaller and smaller pieces.'
#New technique for'seeing'ions at work in a supercapacitor Researchers from the University of Cambridge, together with French collaborators based in Toulouse,
the researchers were able to visualise how ions move around in a supercapacitor. They found that
electrolyte ions are stored in the anode. As the battery discharges, electrolyte ions leave the anode
and move across the battery to chemically react with the cathode. The electrons necessary for this reaction travel through the external circuit,
instead, positive and negative electrolyte ions simply tickto the surfaces of the electrodes when the supercapacitor is being charged.
the ions can easily opoff the surface and move back into the electrolyte. The reason why supercapacitors charge
and discharge so much faster is that the tickingand oppingprocesses happen much faster than the chemical reactions at work in a battery. o increase the area for ions to stick to,
like a carbon sponge, said Griffin. ut it hard to know what the ions are doing inside the holes within the electrode we don know exactly what happens
and the positive ions are attracted to the surface as the supercapacitor charges. But in the positive electrode, an ion xchangehappens,
as negative ions are attracted to the surface, while at the same time, positive ions are repelled away from the surface.
Additionally, the EQCM was used to detect tiny changes in the weight of the electrode as ions enter and leave.
This enabled the researchers to show that solvent molecules also accompany the ions into the electrode as it charges. e can now accurately count the number of ions involved in the charge storage process
and see in detail exactly how the energy is stored, said Griffin. n the future we can look at how changing the size of the holes in the electrode
and the ion properties changes the charging mechanism. This way we can tailor the properties of both components to maximise the amount of energy that is stored.
The next step, said Professor Clare P. Grey, the senior author on the paper, s to use this new approach to understand why different ions behave differently on charging, an ultimately design systems with much higher capacitances. i
#Smart insulin patch could replace injections for diabetes Painful insulin injections could become a thing of the past for the millions of Americans who suffer from diabetes, thanks to a new invention from researchers at North carolina State university and the University
This image portrays the nuclear spin of one of the atoms shown in the full crystal lattice below.
"This small magnetic moment means that little thermal kicks from surrounding atoms or electrons can easily randomize the direction of the nuclear spins.
and their behavior using only a handful of helium ions. The team's technique, published in Physical Review Letters("Strain doping:
This is accomplished by adding a few helium ions into a complex oxide material and provides a never before possible level of control over magnetic and electronic properties."
The method uses a low energy ion gun to add small numbers of helium ions into the material after it has been produced.
Since this time, scientists and engineers have developed many two-dimensional (2d) material innovations--layered materials with the thickness of only one atom or a few atoms.
16 or 32 atoms respectively, said Professor Jim Williams, from the Electronic Material Engineering group at RSPE."
"The semiconductor industry is a multi-billion dollar operation-even a small change in the position of a few silicon atoms has the potential to have a major impact
Perfect graphene an atom-thick sheet of carbon is a conductor, as its atomselectrical charges balance each other out across the plane.
the characteristic that controls how polarized atoms interact with external electric fields. The researchers who published their results this month in the American Chemical Society Journal of Physical chemistry Letters discovered they could calculate the flexoelectric effect of graphene rolled into a cone of any size and length.
The researchers used density functional theory to compute dipole moments for individual atoms in a graphene lattice
in which the balance of positive and negative charges differ from one atom to the next, due to slightly different stresses on the bonds as the diameter changes.
The researchers noted atoms along the edge also contribute electrically, but analyzing two cones docked edge-to-edge allowed them to cancel out,
Lithium-ion cells with cobalt cathodes hold twice the energy of a nickel-based battery and four times that of lead acid.
It is possible for this lithium ion conduction following porous CB 6 to be safer than existing solid lithium electrolyte-based organic-molecular porous-materials utilizing the simple soaking method
only averaging 7. 5 Å a single lithium ion is 0. 76 Å, or. 76 x 10-10 m that runs through them.
The physical structure of the porous CB 6 enables the lithium ions to battery to diffuse more freely than in conventional LIBS
the porous CB 6 solid electrolytes showed impressive lithium ion conductivity. To compare this to existing battery electrolytes,
which can be described as"sheets"with a thickness of a few atoms, strongly differ from their three-dimensional analogues.
"In their structure, the crystals resemble sandwiches with a thickness of three atoms (around 4 angstroms:
a layer of tellurium, a layer of niobium mixed with silicon atoms and then another layer of tellurium.
The ultrahigh-resolution images provide information on the distribution of charges in the electron shells of single molecules and even atoms.
A single silver atom on a silver substrate (Ag (111)) under the scanning quantum dot microscope.
Their properties provide information, for instance, on the distribution of charges in atoms or molecules. For their measurements, the Jlich researchers used an atomic force microscope.
But the large size difference between the tip and the sample causes resolution difficulties if we were to imagine that a single atom was the same size as a head of a pin,
discrete states comparable to the energy level of a single atom. The molecule at the tip of the microscope functions like a beam balance,
comprising only 38 atoms, we can create a very sharp image of the electric field of the sample.
In a nanoscale world and that is our world we can control cellulose-based materials one atom at a time.
"NC State engineer Orlin Velev and colleagues show that silver-ion infused lignin nanoparticles, which are coated with a charged polymer layer that helps them adhere to the target microbes,
then pumped in silicon atoms, which spontaneously crystallize on the wire. Rather than form a uniform shell,
the atoms grow into regularly spaced structures, similar to the droplets that appear when nanowires break down at high temperatures.
The one-atom-thick carbon sheets could revolutionize the way electronic devices are manufactured and lead to faster transistors, cheaper solar cells, new types of sensors and more efficient bioelectric sensory devices.
which ions are accelerated under an electrical field and smashed into a semiconductor. The impacting ions change the physical, chemical or electrical properties of the semiconductor.
In a paper published this week in the journal Applied Physics Letters("Wafer-scale synthesis of multi-layer graphene by high-temperature carbon ion implantation"),from AIP Publishing
Graphene's unique optical, mechanical and electrical properties have lead to the one-atom-thick form of carbon being heralded as the next generation material for faster, smaller, cheaper and less power-hungry electronics."
In the process, carbon ions were accelerated under an electrical field and bombarded onto a layered surface made of nickel, silicon dioxide and silicon at the temperature of 500 degrees Celsius.
and a thin sheet of gold placed a mere 20 atoms away. This field interacts with quantum dots--spheres of semiconducting material just six nanometers wide--that are sandwiched in between the nanocube and the gold.
which are atom-thick latticelike networks of carbon formed into cylinders. Graphene, made from single atom-thick layers of graphite,
was a suitable candidate due its electronic performance and mechanical strength. e knew in theory that
and one oxygen atom) can be polymerized to form polycarbonates in reactions that use special catalysts.
The researchers"doped"zinc oxide with aluminum, meaning the zinc oxide is impregnated with aluminum atoms to alter the material's optical properties.
The water molecules break apart to form hydroxyl groups an atom of oxygen bound to an atom of hydrogen bonded to the materials surface.
where individual electrons in addition to electron pairs bind the individual atoms together. These electrons are confined not to a bond between two atoms.
The electronic loners rather participate in multiple bonds simultaneously: they are bonded resonantly, as physicists say.
they observed that the regular arrangement of the atoms is maintained longer than the electronic structure.
Since the realignment of the atoms causes stress and eventually fractures in the material, the atomic lattice of a substance cannot be rearranged infinitely often.
Now, an international group of researchers has shown how nature uses a variety of pathways to grow crystals that go beyond the classical, one-atom-at-a-time route.
These atoms later become organized by"doing the wave"through the mass to rearrange into a single crystal,
a process known as staple isotope labeling of amino acids in cell cultures and live mice. When examining the nerve cells,
researchers explored whether the H3. 3 variant was labeled with that stable isotope (ewhistones) or if they were free of the label (lderhistones).
Shining a light pulse on to the cavity excited the dye atoms into emitting light in a tightly focused beam.
"Atoms, and the protons and neutrons that make up their nuclei, are familiar terms in science.
and at its ultimate size limit one atom thick, "said Yun Daniel Park, professor in the department of physics and astronomy at Seoul National University.
atoms into graphene. The compounds exhibit an intense blue fluorescence and, consequently, are of interest for use as organic LEDS (OLEDS).
Within the study, boron atoms specifically replaced the two meso carbon atoms within the PAH, which resulted in its ability to transform a near-infrared dye into a blue luminophore.
researchers have become much more capable in their abilities to modify the inner structures by embedding foreign atoms within the carbon network."
The sensor uses a nanoengineered silica chip with an active layer of ions that fluoresce
When the diamond nanoparticles came in contact with the thin sheets of graphene (carbon that's only an atom thick) the graphene rolled up around the diamond nanoparticles,
"We use a larger number of sensors related to ions but got poorer information. These researchers use less sensors,
and this is what scientists have managed now to recreate by carefully tuning the spacing of individual atoms on a surface.
because they have so few atoms to lose. But if scientists could one day work out how to control superlubricity on a larger scale,
and an ion crystal made up of charged atoms held in place using specific voltages and something known as the Coulomb force.
and pull the ion crystal across the lattice, and also adjust the spacing of its atoms.
What they found was that, when the atoms in the ion crystal were spaced out at the same distance as the peaks and troughs of the optical lattice,
they had the most friction, like interlocking Lego bricks getting stuck together and then ripped apart,
But when the team changed the spacing of the ion crystal so that the atoms weren matched up with the optical lattice,
the friction almost entirely disappeared. hat we can do is adjust at will the distance between the atoms to either be matched to the optical lattice for maximum friction,
or mismatched for no friction, said Vuletic. The research has been published in Science. This knowledge could help them to engineer nanomachines that aren worn constantly down by friction,
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