They demonstrated the existence of a quantum-mechanical mixture of electrons and photons, known as a Floquet-Bloch state, in a crystalline solid.
electrons move in a crystal in a regular, repeating pattern dictated by the periodic structure of the crystal lattice.
sprouts a thicket of polymers that attract water, creating an impenetrable barrier for microbes. Its chemical makeup also mimics that of cells important to homeostasis,
Under certain conditions, putting a cracked piece of metal under tension that is, exerting a force that would be expected to pull it apart has the reverse effect,
and professor of materials science and engineering Michael Demkowicz. e had to go back and check, Demkowicz says, when nstead of extending,
The answer turned out to lie in how grain boundaries interact with cracks in the crystalline microstructure of a metal in this case nickel,
A computer simulation of the molecular stucture of a metal alloy, showing the boundaries between microcystalline grains (white lines forming hexagons),
shows a small crack (dark horizontal bar just right of bottom center) that mends itself as the metal is put under stress.
Simulation courtesy of Guoqiang Xu and Michael Demkowicz Most metals are made of tiny crystalline grains
The very idea that crystal grain boundaries could migrate within a solid metal has been studied extensively within the last decade,
the researchers plan to study how to design metal alloys so cracks would close and heal under loads typical of particular applications.
Techniques for controlling the microstructure of alloys already exist, Demkowicz says, so it just a matter of figuring out how to achieve a desired result. hat a field wee just opening up,
The technique might also apply to other kinds of failure mechanisms that affect metals, such as plastic flow instability akin to stretching a piece of taffy until it breaks.
Metal fatigue, for example which can result from an accumulation of nanoscale cracks over time s probably the most common failure modefor structural metals in general
William Gerberich, a professor of chemical engineering and materials science at the University of Minnesota who was involved not in this research,
and its refractive index a measure of how much the material forces light to bend as it passes through.
says Ming Dao, a principal research scientist in MIT Department of Materials science and engineering. Now Dao and colleagues, including Subra Suresh, president of Carnegie mellon University, former dean of MIT School of engineering,
Monica Diez-Silva, a former research scientist in MIT Department of Materials science and engineering; and Gregory Kato of the Department of Medicine at the University of Pittsburgh.
In addition to transmitting different kinds of signals, the new fibers are made of polymers that closely resemble the characteristics of neural tissues,
says Anikeeva, an assistant professor of materials science and engineering. To do that, her team made use of novel fiber-fabrication technology pioneered by MIT professor of materials science
(and paper co-author) Yoel Fink and his team, for use in photonics and other applications.
is the fabrication of polymer fibers hat are soft and flexible and look more like natural nerves.
are made of metals, semiconductors, and glass, and can damage nearby tissues during ordinary movement. t a big problem in neural prosthetics,
These polymer templates, which can have dimensions on the scale of inches, are heated then until they become soft,
John Rogers, a professor of materials science and engineering and of chemistry at the University of Illinois at Urbana-Champaign who was involved not in this research
the Center for Materials science and engineering, the Center for Sensorimotor Neural engineering, the Mcgovern Institute for Brain Research, the U s army Research Office through the Institute for Soldier Nanotechnologies,
and Edelman originally developed this tissue glue several years ago by combining two polymers dextran (a polysaccharide) and a highly branched chain called dendrimer.
the number of keys attached to each polymer, and the ratio of the two polymers, the researchers can tune it to perform best in different types and states of tissue.
An inherent property of the adhesive is that any unused keys are absorbed back into the polymer,
preventing them from causing any undesired side effects. This would allow the researchers to create two
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.
an ion crystal essentially, a grid of charged atoms in order to study friction effects, atom by atom.
To generate the ion crystal, the group used light to ionize, or charge, neutral ytterbium atoms emerging from a small heated oven,
and pull the ion crystal across the lattice, as well as to stretch and squeeze the ion crystal,
much like an accordion, altering the spacing between its atoms. An earthquake and a caterpillarin general, the researchers found that
when atoms in the ion crystal were spaced regularly, at intervals that matched the spacing of the optical lattice, the two surfaces experienced maximum friction,
when the ion crystal as a whole is dragged across the optical lattice, the atoms first tend to stick in the lattice troughs,
If enough force is applied, the ion crystal suddenly slips, as the atoms collectively jump to the next trough. t like an earthquake,
and squeeze the ion crystal to manipulate the arrangement of atoms, and discovered that if the atom spacing is mismatched from that of the optical lattice,
the crystal tends not to stick then suddenly slip, but to move fluidly across the optical lattice,
as the ion crystal is pulled across the optical lattice, one atom may slide down a peak a bit,
says Yet-Ming Chiang, the Kyocera Professor of Ceramics at MIT and a cofounder of 24m (and previously a cofounder of battery company A123).
and colleagues including W. Craig Carter, the POSCO Professor of Materials science and engineering. In this so-called low battery, the electrodes are suspensions of tiny particles carried by a liquid
and plastically deforms to weld the metal together. ach one of these reservoirs, until you open it,
Among nanomaterials, carbon-based nanoparticles such as carbon nanotubes and graphene have shown promising results, but they suffer from relatively low electrical conductivity,
Other groups have made similar supercapacitors using carbon nanotubes or other materials, but the niobium yarns are stronger and 100 times more conductive.
Niobium also has a very high melting point nearly 2 500 degrees Celsius so devices made from these nanowires could potentially be suitable for use in high-temperature applications.
Brandl had synthesized previously polymers that could be cleaved apart by exposure to UV LIGHT. But he and Bertrand came to question their suitability for drug delivery,
because we saw that the particles aggregate once you irradiate them with UV LIGHT. trap for ater-fearingpollutionthe researchers synthesized polymers from polyethylene glycol,
and polylactic acid, a biodegradable plastic used in compostable cups and glassware. Nanoparticles made from these polymers have a hydrophobic core and a hydrophilic shell.
Due to molecular-scale forces in a solution hydrophobic pollutant molecules move toward the hydrophobic nanoparticles,
In that case, both the plastic and the oil-based sauce are hydrophobic and interact together.
hormone-disrupting chemicals used to soften plastics, from wastewater; BPA, another endocrine-disrupting synthetic compound widely used in plastic bottles and other resinous consumer goods, from thermal printing paper samples;
and the polymers are biodegradable, minimizing the risks of leaving toxic secondary products to persist in,
from environmental remediation to medical analysis. The polymers are synthesized at room temperature, and don need to be prepared specially to target specific compounds;
This involved, among other things, switching out gold metals used in manufacturing Gan devices for metals that were compatible with silicon fabrication,
They found that graphene's Hall voltage-a voltage in the perpendicular direction to the current flow-depended linearly on the magnetization of yttrium iron garnet (a phenomenon known as the anomalous Hall effect seen in magnetic materials like iron and cobalt.
Conventional pigments produce colors by selectively absorbing light of different wavelengths#for example red ink appears red
The use of a more cost-effective metal has the potential to move this technology closer to adoption Tan notes.
but it does not contain toxic metals such as cadmium that are known to pose potential risks
#High-resolution patterns of quantum dots with e-jet printing A team of 17 materials science and engineering researchers from the University of Illinois at Urbana#Champaign and Erciyes University in Turkey have authored High-resolution Patterns of Quantum dots
and operating conditions that allow for high-resolution printing of layers of quantum dots with precise control over thickness and submicron lateral resolution and capabilities for use as active layers of QD light-emitting diodes.
Their work on high-resolution patterns of quantum dots is of interest as it shows that advanced techniques in e-jet printing offer powerful capabilities in patterning quantum dot materials from solution inks over large areas.
As for TV technology nearly every TV manufacturer at CES this year remarked Geoffrey Morrison in CNET said quantum dots helped deliver better more lifelike color.
Writing in IEEE Spectrum on Monday Prachi Patel similarly made note that Quantum dots (QDS) are light-emitting semiconductor nanocrystals that used in light-emitting diodes (LEDS) hold the promise of brighter faster displays.
In the IEEE story headlined High-resolution Printing of Quantum dots For Vibrant Inexpensive Displays Patel said these researchers repurposed a printing method which they devised for other applications.
High-resolution Patterns of Quantum dots Formed by Electrohydrodynamic Jet Printing for Light-emitting diodes Nano Lett. Article ASAP.
and operating conditions that allow for high-resolution printing of layers of quantum dots (QDS) with precise control over thickness and submicron lateral resolution and capabilities for use as active layers of QD light-emitting diodes (LEDS).
The technology, developed collaboratively by researchers from Cornell University and Rensselaer Polytechnic institute, uses an electrochemical process called anodization to create nanoscale pores that change the electrical charge and surface energy of a metal surface,
"Anodized metals could be used to prevent buildups of biofilms slick communities of bacteria that adhere to surfaces
Anodized metal could also have marine applications, such as keeping ship hulls free of algae. The collaborating group from Rensselaer Polytechnic institute is led by Diana Borca-Tasciuc, associate professor of mechanical, aerospace and nuclear engineering.
Led by materials science Associate professor Michael Arnold and Professor Padma Gopalan, the team has reported the highest-performing carbon nanotube transistors ever demonstrated.
"Carbon nanotubes are very strong and very flexible, so they could also be used to make flexible displays
"Carbon nanotubes are single atomic sheets of carbon rolled up into a tube. As some of the best electrical conductors ever discovered, carbon nanotubes have long been recognized as a promising material for next-generation transistors,
which are semiconductor devices that can act like an on-off switch for current or amplify current. This forms the foundation of an electronic device.
However, researchers have struggled to isolate purely semiconducting carbon nanotubes, which are crucial, because metallic nanotube impurities act like copper wires and"short"the device.
the UW-Madison team drew on cutting-edge technologies that use polymers to selectively sort out the semiconducting nanotubes,
achieving a solution of ultra-high-purity semiconducting carbon nanotubes. Previous techniques to align the nanotubes resulted in less than-desirable packing density,
the osmium carbonyl clusters can be swapped with other metal carbonyl species to account for different needs and purposes. p
Products that use silica-based nanoparticles for biomedical uses such as various chips drug or gene delivery and tracking imaging ultrasound therapy and diagnostics may also pose an increased cardiovascular
This reality leads to increased human exposure and interaction of silica-based nanoparticles with biological systems.
#Carbon nanoballs can greatly contribute to sustainable energy supply Researchers at Chalmers University of Technology have discovered that the insulation plastic used in high-voltage cables can withstand a 26 per cent higher voltage
a nanomaterial in the fullerene molecular group, provide strong protection against breakdown of the insulation plastic used in high-voltage cables.
It is sufficient to add very small amounts of fullerene to the insulation plastic for it to withstand a voltage that is 26 per cent higher, without the material breaking down,
than the voltage that plastic without the additive can withstand. Carbon nanoballs can greatly contribute to sustainable energy supply An electrical tree,
otherwise destroy chemical bonds in the plastic. Credit: Anette Johansson and Markus Jarvid"Being able to increase the voltage to this extent would result in enormous efficiency gains in power transmission all over the world,
"Using additives to protect the insulation plastic has been known a concept since the 1970s, but until now it has been unknown exactly
Lina Bertling The Chalmers researchers have demonstrated now that fullerenes are the best voltage stabilizers identified for insulation plastic thus far.
and were added to pieces of insulation plastic used for high-voltage cables. The pieces of plastic were subjected then to an increasing electric field until they crackled.
Fullerenes turned out to be the type of additive that most effectively protects the insulation plastic.
and an assistant professor of materials science and engineering at NC State. This could make the manufacture of semiconductor devices an order of magnitude less expensive.
Two studies Complement activation by carbon nanotubes and its influence on the phagocytosis and cytokine response by macrophages and Complement deposition on nanoparticles can modulate immune responses by macrophage B
and T cells found that carbon nanotubes (CNTS) triggered a chain reaction in the complement system which is part of the innate immune system
and metal when an intermediate layer of vanadium is present.##The simplicity of the technique and the universality of the mechanism open a new avenue for the growth of nanowire arrays of a variety of materials.
Surface energy induced formation of single crystalline bismuth nanowires over vanadium thin film at room temperature. Nano Letters 14 5630#5635 (2014) DOI:
#Contact lens merges plastics and active electronics via 3-D printing (Phys. org) As part of a project demonstrating new 3-D printing techniques Princeton researchers have embedded tiny light-emitting diodes into a standard contact lens
The researchers used tiny crystals called quantum dots to create the LEDS that generated the colored light.
We used the quantum dots also known as nanoparticles as an ink Mcalpine said. We were able to generate two different colors orange and green.
and polymers without the involvement of conventional microfabrication techniques yet the thickness and uniformity of the printed films are two of the critical parameters that determine the performance
For this they developed a simple procedure to produce polymer vesicles small artificial bubbles with host cell receptors on the surface.
The preparation of such polymer vesicles with water-soluble host receptors was done by using a mixture of two different block copolymers.
The NC State researchers took a different approach placing nanoscale polystyrene spheres on the surface of the photosensitive film.
For this work we focused on creating nanostructures using photosensitive polymers which are used commonly in lithography Zhang says.
We're exploring the use of nanosphere materials other than polystyrene as well as nanoparticle shapes other than spheres Chang says.
#Atomic'mismatch'creates nano'dumbbells'Like snowflakes nanoparticles come in a wide variety of shapes and sizes.
and polymers. A paper describing this discovery by a research team led by John V. Badding a professor of chemistry at Penn State was published in the Sept. 21 issue of the journal Nature Materials.
so that when we release the pressure very slowly an orderly polymerization reaction happens that forms the diamond-core nanothread.
This is very straightforward rapid'cooking'of a metal-organic precursor in boiling water. The precursor compound is a solid tin alkoxide a material analogous to cost-efficient and broadly available titanium alkoxides.
Scientists create multifunctional nanotubes using nontoxic materials A doctoral student in materials science at Technische Universitat Darmstadt is making multifunctional nanotubes of goldith the help of Vitamin c and other harmless substances.
She precipitates the precious metal from an aqueous solution onto a pretreated film with many tiny channels.
The metal on the walls of the channels adopts the shape of nanotubes; the film is dissolved then.
"She preferred not to use cyanide, formaldehyde, arsenic and heavy metal salts. She was inspired by a journal article by researchers who achieved silver precipitation using coffee.
Although tests with bio-based plastics are already on the agenda, the films still consist of polycarbonate also made or of polyethylene terephthalate (PET).
In order to create the miniature plastic channels that define the shape, a round film is bombarded vertically with an ion beam.
Each ion leaves a straight track in the film which then becomes a small hole,
"Nano meets Life"is the second motto of the TU Materials science researchers. For example, they are thinking about also using the nanotubes to measure blood sugar."
The nanoparticles naturally grow a hard shell of silicon oxide on their surface much like stainless steel forms a protective layer of chromium oxide on its surface.
and zinc metals a combination discovered for the first time. These are heated to a high temperature in the presence of a flow of carbon dioxide to produce a controlled metallothermic reaction.
or metals while attempting to sense light. Additionally the new material is capable of higher spatial resolution
The researchers combined semiconductor nanorods and carbon nanotubes to create a wireless light-sensitive flexible film that could potentially replace a damaged retina.
"We believe that the results of this work are an important contribution to the use of inelastic electron tunnelling spectroscopy that will allow the technique to be used as an additional source of information in materials science
The materials commonly used for restoration such as coatings of synthetic polymers or inorganic materials have a different composition than that of the original artefacts
or exhibit a complex composition they can be classified as composite materials which means that you need materials science
and colloid and surface science to understand and eventually rescue these materials from possible degradation processes.
and vinyl polymers that seriously damage the painting and in many cases have led to the loss of painted surfaces.
and materials for modern and contemporary works of art such as acrylic paintings plastic sculptures and composite works that include metal textiles polymers etc.
In order to address this challenge we have created a unique partnership that groups research institutions and materials science experts together with high-profile museums conservation centres and experienced professionals in the field of modern art preservation.
Despite the pessimistic prognosis the researchers found that protons pass through the ultra-thin crystals surprisingly easily especially at elevated temperatures
and its sister material boron nitride attractive for possible uses as proton-conducting membranes which are at the heart of modern fuel cell technology.
or monolayer boron nitride can allow the existing membranes to become thinner and more efficient with less fuel crossover and poisoning.
#Researchers develop efficient method to produce nanoporous metals Nanoporous metals foam-like materials that have some degree of air vacuum in their structure have a wide range of applications because of their superior qualities.
Nanoporous metals offer an increased number of available sites for the adsorption of analytes a highly desirable feature for sensors.
Lawrence Livermore National Laboratory (LLNL) and The swiss Federal Institute of technology (ETH) researchers have developed a cost-effective and more efficient way to manufacture nanoporous metals over many scales from nanoscale to macroscale
A coating of metal is added and sputtered across the wafer. Gold silver and aluminum were used for this research project.
However the manufacturing process is limited not to these metals. Next a mixture of two polymers are added to the metal substrate to create patterns a process known as diblock copolymer lithography (BCP.
The pattern is transformed in a single polymer mask with nanometer-size features. Last a technique known as anisotropic ion beam milling (IBM) is used to etch through the mask to make an array of holes creating the nanoporous metal.
During the fabrication process the roughness of the metal is examined continuously to ensure that the finished product has good porosity
which is key to creating the unique properties that make nanoporous materials work. The rougher the metal is the less evenly porous it becomes.
During fabrication our team achieved 92 percent pore coverage with 99 percent uniformity over a 4-in silicon wafer which means the metal was smooth
and evenly porous said Tiziana Bond an LLNL engineer who is a member of the joint research team.
and metal surface roughness-by which the fabrication of nanoporous metals should be stopped when uneven porosity is known the outcome saving processing time and costs.
The real breakthrough is created that we a new technique to manufacture nanoporous metals that is cheap
and can be done over many scales avoiding the lift off technique to remove metals with real-time quality control Bond said.
These metals open the application space to areas such as energy harvesting sensing and electrochemical studies. The lift off technique is a method of patterning target materials on the surface of a substrate by using a sacrificial material.
Other applications of nanoporous metals include supporting the development of new metamaterials (engineered materials) for radiation-enhanced filtering
The high temperature processes essential for high performance electronic devices have restricted severely the development of flexible electronics because of the fundamental thermal instabilities of polymer materials.
A research team headed by Professor Keon Jae Lee of the Department of Materials science and engineering at KAIST provides an easier methodology to realize high performance flexible electronics by using the Inorganic-based Laser Lift off (ILLO.
because the pores are too small for optical microscopy and too flexible and mobile for X-ray crystallography."
First they made a sandwich composed of two metal electrodes separated by a two-nanometer thick insulating layer (a single nanometer is 10000 times smaller than a human hair) made by using a semiconductor technology called atomic layer deposition.
The results of the UC work will be presented at the Materials Research Society Conference in Boston Nov 30-Dec 5 by Andrew Dunn doctoral student in materials science engineering in UC's College of Engineering and Applied science.
Working with Dunn in this study are Donglu Shi professor of materials science engineering in UC's College of Engineering and Applied science;
Unlike other new biomarkers used for imaging such as quantum dots the NTU biomarker has also been shown to be nontoxic staying in the body for up to two days before it is passed out harmlessly.
Moving forward the team from NTU's School of Materials science and engineering will be looking to load multiple layers of drugs into their biomarker.
Quantum dots are light-emitting semiconductor nanocrystals that can be tuned by changing their size, nanometer by nanometer to emit all colors across the visible spectrum.
filled with quantum dots tuned to red and green, that implemented during the synthesis process. Manufacturers use a blue LED in the backlight,
on implementing quantum dots into electronic devices. In a study funded by MIT Deshpande Center for Technological Innovation, Coe-Sullivan, QD Vision cofounder Jonathan Steckel Phd 6,
To do so, they sandwiched a layer of quantum dots, a few nanometers thick, between two organic thin films.
and Asus has a quantum dot notebook. nd there nothing in between that quantum dots can address,
These polymer-based nanocomposites are reinforced with graphite nanoplatelets for use in industry. Nanocomposites are formed by two
or more constituents in this case the polymer and a nano-sized reinforcing material: the graphite nanoplatelets s
"The breakthrough extends a stream of nanotechnology research at Rice that began with chemist Robert Hauge's 2009 invention of a"flying carpet"technique to grow very long bundles of aligned carbon nanotubes.
At issue are molybdenum sulfide (Mos2) thin films that are only one atom thick first developed by Dr. Linyou Cao an assistant professor of materials science and engineering at NC State.
nanoparticles comprised of a nontoxic biodegradable polymer matrix and insect derived double-stranded ribonucleic acid or dsrna.
This has a tremendous impact for many scientific areas including materials science chemistry and energy materials said co-author Volker Rose.
Even in its present form the techniques demonstrated here can revolutionize nanoscale imaging in realms far beyond materials science including electronics and biology.
Today it signals a promising discovery in materials science research that could help next-generation technology-like wearable energy storage devices-get off the ground.
and can be contorted into a variety of shapes is a rarity in the field of materials science.
Tensile strength-the strength of the material when it is stretched -and compressive strength-its ability to support weight-are valuable characteristics for these materials because at just a few atoms thick their utility figures almost entirely on their physical versatility.
Take the electrode of the small lithium-ion battery that powers your watch for example ideally the conductive material in that electrode would be very small
or tensile strength-we open a new world of possibilities. This flexible new material which the group has identified as a conductive polymer nanocomposite is the latest expression of the ongoing research in Drexel's Department of Materials science and engineering on a family of composite two-dimensional materials called MXENES.
This development was facilitated by collaboration between research groups of Yury Gogotsi Phd Distinguished University and Trustee Chair professor in the College of Engineering at Drexel and Jieshan Qiu vice dean for research
Zheng Ling a doctoral student from Dalian spent a year at Drexel spearheading the research that led to the first MXENE-polymer composites.
To produce the flexible conductive polymer nanocomposite the researchers intercalated the titanium carbide MXENE with polyvinyl alcohol (PVA)- a polymer widely used as the paper adhesive known as school
They also intercalated with a polymer called PDDA (polydiallyldimethylammonium chloride) commonly used as a coagulant in water purification systems.
The uniqueness of MXENES comes from the fact that their surface is full of functional groups such as hydroxyl leading to a tight bonding between the MXENE flakes and polymer molecules while preserving the metallic conductivity of nanometer-thin
When mixing MXENE with PVA containing some electrolyte salt the polymer plays the role of electrolyte
ions also stay trapped near the MXENE flakes by the polymer. With these conductive electrodes and no liquid electrolyte we can eventually eliminate metal current collectors
and polymer will affect the properties of the resulting nanocomposite and also exploring other MXENES and stronger and tougher polymers for structural applications.
Explore further: Crumpled graphene could provide an unconventional energy storag g
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