or how to reliably predict it is comingsays Ming Dao a principal research scientist in MIT Department of Materials science and 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.
said study co-author Michael Mcgehee, a professor of materials science and engineering at Stanford. ight now, silicon solar cells dominate the world market,
so Bailie did it manually. e used a sheet of plastic with silver nanowires on it, he said. hen we built a tool that uses pressure to transfer the nanowires onto the perovskite cell, kind of like a temporary tattoo.
The BAT key enabling technologies include a novel aerodynamic design, custom-made composite materials and an innovative control system.
The Rice lab of chemist James Tour discovered last year that firing a laser at an inexpensive polymer burned off other elements and left a film of porous graphene, the much-studied atom-thick
since their work to make vertically aligned supercapacitors with laser-induced graphene on both sides of a polymer sheet.
Tour is the T. T. and W. F. Chao Chair in Chemistry as well as a professor of materials science and nanoengineering and of computer science and a member of the Richard E. Smalley Institute for Nanoscale Science and Technology.
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 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
However, researchers have struggled to isolate purely semiconducting carbon nanotubes, which are crucial, because metallic nanotube impurities act like copper wires and hortthe 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,
Additional authors on the ACS Nano paper include UW-Madison materials science and engineering graduate students Gerald Brady, Yongho Joo and Matthew Shea,
Purdue University researchers had created previously uperlatticesfrom layers of the metal titanium nitride and the dielectric, or insulator, aluminum scandium nitride.
which rely on the use of noble metals such as gold and silver, the new metamaterial is compatible with the complementary metalxideemiconductor manufacturing process used to construct integrated circuits.
#New catalyst process uses light not metal for rapid polymerization A team of chemistry and materials science experts from University of California,
Santa barbara and The Dow chemical Company has created a novel way to overcome one of the major hurdles preventing the widespread use of controlled radical polymerization.
In a global polymer industry valued in the hundreds of billions of dollars, a technique called Atom Transfer Radical Polymerization is emerging as a key process for creating well-defined polymers for a vast range of materials, from adhesives to electronics.
However, current ATRP methods by design use metal catalysts a major roadblock to applications for which metal contamination is an issue,
This new method of radical polymerization doesn involve heavy metal catalysts like copper. Their innovative, metal-free ATRP process uses an organic-based photocatalyst
How can we do this without any metals? said Craig Hawker, director of the Dow Materials Institute at UCSB. e looked toward developing an organic catalyst that is highly reducing in the excited state,
Their study was recently detailed in a paper titled etal-Free Atom Transfer Radical Polymerization, published in the Journal of the American Chemical Society.
but the new metal-free rapid polymerization process ushes controlled radical polymerization into new areas and new applications, according to Hawker. any processes in use today all start with ATRP.
Controlling radical polymerization processes is critical for the synthesis of functional block polymers. As a catalyst, phenothiazine builds block copolymers in a sequential manner,
achieving high chain-end fidelity. This translates into a high degree of versatility in polymer structure,
as well as an efficient process. ur process doesn need heat. You can do this at room temperature with simple LED LIGHTS,
said Hawker. ee had success with a range of vinyl monomers, so this polymerization strategy is useful on many levels. he development of living radical processes,
such as ATRP, is arguably one of the biggest things to happen in polymer chemistry in the past few decades,
he added. his new discovery will significantly further the whole field. w
#Chemists one step closer to new generation of electric car battery Lithium sulphur (Li-S) batteries can theoretically power an electric car three times further than current lithium-ion batteries for the same weight at much
These are the reasons why carbon fiber-reinforced plastics (CFRPS) have still not yet found their path into wide-scale serial production so far to date.
however if composite materials have to be processed. his is why from a materials engineering perspective we optimize the surfaces of the fiberssays Endres.
Because when it comes to recycling fiber composite materials are a proverbial ough nut to crack.
Fibers inside these parts are embedded into a thermoplastic matrix#plastic that is which can be shaped at ultra-high temperatures
Solid Polymer Ionic Liquid (SPIL) electrolyte enables the ultra-thin lithium metal anode and improves the cell-level energy density by 50%compared to graphite anodes
parallel batches and then an array of them is transferred onto a thin sheet of glass or plastic.
and their wiring consists of acrylic plastic or Plexiglas, this system has the potential to be inexpensive to produce.
Even though the printed plastic lenses were not up to specification, they were able to demonstrate over 100 times solar concentration.
John A Rogers, professor of materials science and engineering, University of Illinois, Urbana Champaign; and Bram M. Meulblok, technical representative, LUXEXCEL Group B. V.,The netherlands.
#One-atom-thin silicon transistors hold promise for super-fast computing Researchers at The University of Texas at Austin Cockrell School of engineering have created the first transistors made of silicene, the world thinnest silicon material.
silicene has outstanding electrical properties but has until now proved difficult to produce and work with.
solved one of the major challenges surrounding silicene by demonstrating that it can be made into transistors emiconductor devices used to amplify and switch electronic signals and electrical power.
Until a few years ago, human-made silicene was a purely theoretical material. Looking at carbon-based graphene
Akinwande, who also works on graphene transistors, sees value in silicene relationship to silicon, which chipmakers already know how to work with. part from introducing a new player in the playground of 2-D materials, silicene,
with its close chemical affinity to silicon, suggests an opportunity in the road map of the semiconductor industry,
Akinwande said. he major breakthrough here is the efficient low-temperature manufacturing and fabrication of silicene devices for the first time.
silicene has proved extremely difficult to create and work with because of its complexity and instability when exposed to air.
to develop a new method for fabricating the silicene that reduces its exposure to air.
They then formed a silicene sheet on a thin layer of silver and added a nanometer-thick layer of alumina on top.
They were then able to gently scrape some of the silver to leave behind two islands of metal as electrodes, with a strip of silicene between them.
and methods for creating silicene, which may lead to low energy, high-speed digital computer chips p
#Graphene displays clear prospects for flexible electronics Published in the scientific journal Nature Materials, University of Manchester and University of Sheffield researchers show that new 2d esigner materialscan be produced to create flexible, see-through and more efficient electronic devices.
The LED device was constructed by combining different 2d crystals and emits light from across its whole surface.
we show that they can provide the basis for flexible and semitransparent electronics. he range of functionalities for the demonstrated heterostructures is expected to grow further on increasing the number of available 2d crystals
By constructing tiny irrorsto trap light around impurity atoms in diamond crystals, the team dramatically increased the efficiency with
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.
or even to growing arrays of carbon nanotubes, which his group is also studying. his is high-quality research that represents significant progress on the path to scalable production methods for large-area graphene,
they will be manufactured from polymer-lined 5 mm-thick carbon fibre in the finished model. The lightweight lithium-polymer hybrid fuel cell that converts the hydrogen gas into electricity to power the rotors was developed by a sister company,
called Horizon Energy systems. y removing the design silos that typically separate the energy storage component from UAV frame development,
But many of the advances rely on petroleum-based plastics and toxic materials. Yu-Zhong Wang, Fei Song and colleagues wanted to seek a reenerway forward.
and infused it with biocompatible quantum dots tiny, semiconducting crystals made out of zinc and selenium.
The paper glowed at room temperature and could be rolled and unrolled without cracking. Source: AC c
the team is also considering the use of other metals, such as zinc and magnesium that could serve as the anode in a battery of this type. e also expect that other organometallic compounds with multi-valence-state metal centers (redox centers) may also function as the anode,
surface smoothness and thermal expansion. ou don want it to expand or shrink too much. Wood is a natural hydroscopic material
Gong and her students also have been based studying bio polymers for more than a decade. CNF offers many benefits over current chip substrates, she says. he advantage of CNF over other polymers is that it a bio-based material and most other polymers are based petroleum polymers.
Bio-based materials are sustainable biocompatible and biodegradable, Gong says. nd, compared to other polymers,
CNF actually has a relatively low thermal expansion coefficient. The group work also demonstrates a more environmentally friendly process that showed performance similar to existing chips.
The majority of today wireless devices use gallium arsenide-based microwave chips due to their superior high-frequency operation and power handling capabilities.
a Swanlund Chair in Materials science and engineering, have developed a line of heat-triggered, self-destructing devices, a step toward greatly reducing electronic waste and boosting sustainability in device manufacturing.
In the normal non-superconducting phase, the electrons in most metals move independentlyhe scattering of electrons causes electrical resistance.
The researchers used quantum dots in strontium titanate to observe the electron pairs. Quantum dots are small regions of a material in
which the number of electrons can be controlled precisely, in this case using an electrostatic gate. The quantum dots were large enough to support a superconducting phase at low temperatures
but the researchers observed that the dots always preferred an even number of electrons in the new phase at higher temperatures.
and measured 58 quantum dots with varying dimensions and barriers between the quantum dots and the leads.
we noticed that it was almost invisible and very flexible like a polymer and could literally be sucked into a glass needle or pipette.
researchers lay out a mesh of nanowires sandwiched in layers of organic polymer. The first layer is dissolved then, leaving the flexible mesh,
#Single Atom Building blocks For Future Electronics The material is called a silicene, a layer of silicon single atoms arranged in a honeycomb pattern that was fabricated first by researchers at UOW Institute for Superconducting and Electronic Materials (ISEM) and their partners in Europe and China.
and Dr Yi Du have published breakthrough research into a new material call silicene. An ISEM team led by Professor Shi Xue Dou
and Dr Yi Du have published breakthrough research into a new material call silicene. Silicene great promise is related to how electrons can streak across it at incredible speed
close to the speed of light. Propelling the electrons in silicene requires minimal energy input, which means reducing power and cooling requirements for electronic devices. f silicene could be used to build electronic devices,
it could enable the semiconductor industry to achieve the ultimate in miniaturization, Dr Yi Du,
a research fellow at the ISEM, said. The difficulty for researchers, according to Dr Du, is that up until a couple of years ago,
was the first research group in Australia to make silicene and recently, using state-of-the-art equipment,
and modifying silicene so it can be integrated it into ultra-small renewable energy devices, such as solar cells,
data storage hardware and advancing quantum computing. uow195685 o one in the scientific community believed silicene paper could be made
and place them one at a time on a plate to form the silicene paper. he process is like laying bricks,
and high-quality silicene layers that are large enough for integrated circuits, Dr Du said. here is also work to be done in developing ways to peel
and transfer the silicene layers from the base it has been assembled on, as well as embed electrodes in it. s
who recently completed his Phd in materials science and engineering at Illinois. pin transfer torque has often been realized by passing electrical currents through magnetic layers.
The global market for polymers such as this approaches $7 billion, and there are estimates the U s. spends up to $120 billion a year on probiotic products such as yogurt, sour cream and buttermilk.
beginning in the early 1990s when a novel polymer with an ability to rapidly thicken milk was discovered by an OSU microbiologist.
The polymer is known as Ropy 352 and produced by a non-disease-causing bacterium. his is one of many naturally occurring,
never-before reported grouping of genes that code for a unique polymer that naturally thickens milk.
In basic research, wee also broadened our understanding of how and why non-disease-causing bacteria produce polymers.
This polymer appears to give fermented foods a smooth thick, creamy property, and may initially find uses in sour cream, yogurt, kefir, buttermilk, cream cheese and artisan soft cheeses.
And unlike other polymers that are used now commonly as thickeners, it may add probiotic characteristics to foods,
non-disease-causing bacterial strains that produce unique polymers with characteristics desirable and safe for food products,
One of the most common polymers, xanthum gum, has been in use since 1969 and is found in a huge range of food products, from canned foods to ice cream, pharmaceuticals and beauty products.
Trempy research program has determined the new polymer will thicken whole and nonfat milk, lactose-free milk, coconut milk, rice milk,
Beyond that, the polymer may have a wide range of applications such as thickening of pharmaceuticals, nutraceuticals, fruit juices, cosmetics and personal care products.
In their broader uses, microbial polymers are used for food production, chemical production, detergents, cosmetics, paints, pesticides, fertilizers, film formers, lubricants, explosives, pharmaceutical production and waste treatment.
Polymer material produced by a 3-D printer includes soft, flexible material (clear or lighter tone) with particles of hard material (black) embedded, in predetermined arrangements.
involves a material that is composed of two different polymers with different degrees of stiffness: More rigid particles are embedded within a matrix of a more flexible polymer.
When squeezed, the material surface changes from smooth to a pattern determined by the spacing and shapes of the implanted harder particles;
or its reflectivity. But by arranging the distribution of the hard particles, it can also be used to produce highly complex surface textures for example,
#Centimeter-long origami robot At the recent International Conference on Robotics and Automation, MIT researchers presented a printable origami robot that folds itself up from a flat sheet of plastic
The middle layer always consisted of polyvinyl chloride, a plastic commonly used in plumbing pipes, which contracts when heated.
In the acetone-soluble prototype, the outer layers were polystyrene. Slits cut into the outer layers by a laser cutter guide the folding process.
If two slits on opposite sides of the sheet are of different widths then when the middle layer contracts, it forces the narrower slit edges together,
which a tiny layer of magnetic material is sandwiched between tantalum and tantalum-oxide layers. Long stripes of magnetic domains appear in the magnetic material on one side of a tiny channel.
When the scientists applied an electric current to the metal layers, the stripes stretched through the channel
have the right boiling point distribution and lubricity, and a very low pour point, meaning the fuel can become gelatinous in the cold temperatures of the stratosphere,
rare-earth metals are, as their name suggests, hard to come by. Mining and purifying them is an expensive,
Researchers at the University of Pennsylvania have pioneered now a process that could enable the efficient recycling two of these metals, neodymium and dysprosium.
and Patrick J. Carroll, director of the University of Pennsylvania X-ray Crystallography Facility, also contributed to the study.
the two metals need to be separated and remixed before they can be reused. t, in principle, easier to get the neodymium
The technique, known as liquid-liquid extraction, involves dissolving the composite material and chemically filtering the elements apart.
The process is repeated thousands of times to get useful purities of the rare-earth metals,
Rather than this liquid-liquid method, Schelter team has devised a way to separate the two metals by having neodymium stay dissolved in a solution
enabling the two metals to be separated easily. Once apart, an acid bath can strip the ligand off both metals,
enabling it to be recycled as well. f you have the right ligand, you can do this separation in five minutes,
so it is less likely to fall off before the metals are separated. Further modification of the ligand could enable other rare earths in technology products,
and co-first author Crystal S. Conn, Phd, a postdoctoral fellow in the UCSF Department of Urology,
The scientists devised a new arrangement of solar cell ingredients, with bundles of polymer donors (green rods) and neatly organized fullerene acceptors (purple, tan.
There is currently a big push to make lower-cost solar cells using plastics, rather than silicon,
you can vastly improve the retention of energy. he two components that make the UCLA-developed system work are a polymer donor and a nanoscale fullerene acceptor.
The polymer donor absorbs sunlight and passes electrons to the fullerene acceptor; the process generates electrical energy.
The plastic materials, called organic photovoltaics, are organized typically like a plate of cooked pasta a disorganized mass of long, skinny polymer paghettiwith random fullerene eatballs.
because the electrons sometimes hop back to the polymer spaghetti and are lost. The UCLA technology arranges the elements more neatly like small bundles of uncooked spaghetti with precisely placed meatballs.
The fullerenes inside the structure take electrons from the polymers and toss them to the outside fullerene
which can effectively keep the electrons away from the polymer for weeks. hen the charges never come back together,
these particles are coated with polymers, which fine-tune their optical properties and their rate of degradation in the body.
These polymers can be loaded with drugs that are released gradually. Finally, carbon nanoparticles are rather small, less than eight nanometres in diameter (in comparison,
Scientists also found that they can alter the infusion of the particles into melanoma cells by adjusting the polymer coatings.
Scientists say that they can be coated with different polymers to give them different optical properties to make them even easier to detect in the organism,
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
a conductive polymer material that responds to electromagnetic fields. Wen Gao, a postdoctoral researcher in the Center for Paralysis Research who worked on the project with Borgens,
The nanowire patches adhere to the site of injury through surface tension, Gao said. The magnitude and wave form of the electromagnetic field must be tuned to obtain the optimum release of the drug
and the shape change of the polymer that allows it to store and release drugs,
the polymer snaps back to the initial architecture and retains the remaining drug molecules . or each different drug the team would need to find the corresponding optimal electromagnetic field for its release,
which interact with each other within the silica fiber optic cables. The researchers note that this approach could be used in systems with far more communication channels.
and Steven P. Levitan, Phd, John A. Jurenko Professor of Electrical and Computer engineering, integrated models for self-oscillating polymer gels and piezoelectric micro-electric-mechanical systems to devise a new
and detected using ferromagnetic metal contacts with a tunnel barrier consisting of single layer graphene between the metal and silicon NW.
The ferromagnetic metal/graphene tunnel barrier contacts used to inject and detect spin appear as blue,
which depend critically on the interface resistance between a ferromagnetic metal contact and the NW.
and compatibility with both the ferromagnetic metal and silicon NW. Using intrinsic 2d layers such as graphene
or hexagonal boron nitride as tunnel contacts on nanowires offers many advantages over conventional materials deposited by vapor deposition (such as Al2o3
The use of multilayer rather than single layer graphene in such structures may provide much higher values of the tunnel spin polarization because of band structure derived spin filtering effects predicted for selected ferromagnetic metal/multi
and Dr. Berend Jonker from the Materials science and Technology Division, and Dr. Jeremy Robinson from the Electronics Science and Technology Division i
When pressure is increased in the pores of the polymer, the structure swells and expands in a preferred direction.
The walls of the cells are made of a non-swellable polymer; a swellable polymer fills the interior of the chambers.
If the pressure inside the cells increases, for example, because the swellable polymer absorbs liquids, the structure expands in one direction.
Advanced Materials Interfaces/MPI of Colloids and Interfacesif you enjoy walking in the woods, you may well be familiar with the phenomenon.
To this end, they developed a computer simulation as well as tissue-like materials from a porous polymer in
Moveable parts of such robots, the actuators, might consist of a porous polymer with precisely defined pore properties. he actual motion could then be controlled by compressed air or an expandable fluid in the pores
The researchers were delighted also that the theoretical predictions from the computer simulation almost perfectly matched the results of their tests on synthesized porous polymer materials.
says Dunlop. Synthetic polymer honeycomb structures from a 3d printerthe composition of the cell walls plays a key role in the expansion process in the relevant cells of pinecones
The researchers simulated this structure for their practical experiments by bonding two different swellable polymer layers together.
The scientists envisage using porous polymer materials whose pores are filled with a hygroscopic fluid, for example a superabsorbing hydrogel, in future practical applications.
Carbon nanotubes, seamless cylinders of graphene, do not display a total dipole moment, he said. While not zero, the vector-induced moments cancel each other out.
but they anticipate the technique will be widely applicable to both functionality driven materials science research
The study was supported by the Department of energy Office of Science and used resources at the Center for Nanophase Materials sciences, a DOE Office of Science User Facility at ORNL.
Scientists from PML Semiconductor and Dimensional Metrology Division have performed studies on the way the interface between a ferromagnetic material (cobalt)
This is helpful in efficient injection of the spin-polarized charge carrier from ferromagnetic materials to organic materials.
#Polymer mold makes perfect silicon nanostructures Using molds to shape things is as old as humanity.
In the Bronze age, the copper-tin alloy was melted and cast into weapons in ceramic molds.
In a breakthrough for nanoscience, Cornell polymer engineers have made such a mold for nanostructures that can shape liquid silicon out of an organic polymer material.
The advance is from the lab of Uli Wiesner, the Spencer T. Olin Professor of Engineering in the Department of Materials science and engineering,
whose lab previously has led the creation of novel materials made of organic polymers. With the right chemistry, organic polymers self-assemble,
and the researchers used this special ability of polymers to make a mold dotted with precisely shaped and sized nanopores..
Normally, melting amorphous silicon, which has a melting temperature of about 2, 350 degrees, would destroy the delicate polymer mold,
which degrades at about 600 degrees. But the scientists, in collaboration with Michael Thompson, associate professor of materials science and engineering, got around this issue by using extremely short melt periods induced by a laser.
The researchers found the polymer mold holds up if the silicon is heated by laser pulses just nanoseconds long.
At such short time scales, silicon can be heated to a liquid, but the melt duration is so short the polymer doesn have time to oxidize
and decompose. They essentially tricked the polymer mold into retaining its shape at temperatures above its decomposition point.
When the mold was etched away, the researchers showed that the silicon had been shaped perfectly by the mold.
This could lead to making perfect, single-crystal silicon nanostructures. They haven done it yet,
In materials science, the goal is always to get well-defined structures that can be studied without interference from material defects.
Discovery of single-crystal silicon the semiconductor in every integrated circuit made the electronics revolution possible.
It took cutting single crystals into wafers to truly understand silicon semiconducting properties. Today, nanotechnology allows incredibly detailed nanoscale etching, down to 10 nanometers on a silicon wafer.
Semiconductors like silicon don self-assemble into perfectly ordered structures like polymers Do it almost unheard of to get a 3-D structured single crystal of a semiconductor.
porous nanomaterials using specially structured molecules called block copolymers. They first used a carbon dioxide laser in Thompson lab to ritethe nanoporous materials onto a silicon wafer.
contained a block copolymer, which directed the assembly of a polymer resin. Writing lines in the film with the laser,
the block copolymer decomposed, acting like a positive-tone resist, while the negative-tone resin was left behind to form the porous nanostructure.
That became the mold. e demonstrated that we can use organic templates with structures as complicated as a gyroid, a periodically ordered cubic network structure,
Overtext Web Module V3.0 Alpha
Copyright Semantic-Knowledge, 1994-2011