and films studded with quantum dots or tiny crystals that exhibit quantum mechanical properties. They also engineered the cells
During the first stage, pigments such as chlorophyll absorb light, which excites electrons that flow through the thylakoid membranes of the chloroplast.
When the target molecule binds to a polymer wrapped around the nanotube, it alters the tube fluorescence. e could someday use these carbon nanotubes to make sensors that detect in real time, at the single-particle level,
and the polymer ring that protects the electronics in the fish s guts. The long haulthe fish can perform 20
The MIT team found that they could create novel sensors by coating the nanotubes with specifically designed amphiphilic polymers polymers that are drawn to both oil and water, like soap.
or diabetes in living systems. his new technique gives us an unprecedented ability to recognize any target molecule by screening nanotube-polymer complexes to create synthetic analogs to antibody function,
Synthetic antibodies The new polymer-based sensors offer a synthetic design approach to the production of molecular recognition sites enabling, among other applications, the detection of a potentially infinite library of targets.
Their approach takes advantage of a phenomenon that occurs when certain types of polymers bind to a carbon nanotube.
These polymers, known as amphiphilic, have both hydrophobic and hydrophilic regions. These polymers are designed and synthesized such that
when the polymers are exposed to carbon nanotubes, the hydrophobic regions latch onto the tubes like anchors
and the hydrophilic regions form a series of loops extending away from the tubes. These loops form a new layer surrounding the nanotube, known as a corona.
and the polymer before it attaches to the nanotube. he idea is that a chemist could not look at the polymer
because the polymer itself can selectively recognize these molecules. It has to adsorb onto the nanotube and then,
by having certain sections of the polymer exposed, it forms a binding site, Strano says.
The researchers used an automated, robot-assisted trial and error procedure to test about 30 polymer-coated nanotubes against three dozen possible targets, yielding three hits.
They are now working on a way to predict such polymer-nanotube interactions based on the structure of the corona layers,
and their targets. hat happening to the polymer and the corona phase has been a bit of a mystery,
as well as for processes such as spray cooling of hot metal. One application now being considered by Varanasi
In 2006, Doyle lab developed a way to create huge batches of identical particles made of hydrogel, a spongy polymer.
From metals to drugsthe researchers now hope to explore mitochondrial-targeted cisplatin s potential use as a chemotherapy drug by testing it in animals.
They also plan to try targeting cisplatin and other metal-based drugs to different parts of cells
Cisplatin and a handful of other platinum drugs are the only metal-based drugs now approved for human use
but researchers around the world are working on other types of metal-based drugs. People are interested really in using metals as therapeutics
but they re difficult to control and elucidating the cellular targets of metal-based drugs is challenging
because they can interact with so many different biomolecules Radford says. By targeting specific cellular organelles with the same therapeutic molecules we can learn a lot about how the cells respond to a given compound
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,
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
In addition to transmitting different kinds of signals, the new fibers are made of polymers that closely resemble the characteristics of neural tissues,
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,
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 plastically deforms to weld the metal together. ach one of these reservoirs, until you open it,
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
"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.
the UW-Madison team drew on cutting-edge technologies that use polymers to selectively sort out the semiconducting nanotubes,
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 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.
#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.
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.
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,
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 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 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.
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.
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.
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
nanoparticles comprised of a nontoxic biodegradable polymer matrix and insect derived double-stranded ribonucleic acid or dsrna.
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.
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
#Microtubes create cozy space for neurons to grow and grow fast Tiny, thin microtubes could provide a scaffold for neuron cultures to grow
Very thin membranes of silicon nitride roll themselves up into tubes of precise dimensions. The tubes are about as wide as the cells
The thin silicon nitride tubes are transparent, so researchers can watch the live neuron cells as they grow using a conventional microscope."
The nanocarriers are made from a polymer called polyethylene glycol (PEG) to which researchers attach the cancer-killing drug camptothecin (CPT) like bunches of grapes on a vine.
I did research on conducting plastics for electronic devices. When I moved into the cancer treatments with nanotechnology that's when my mum became really excited about my work.
Using electron beam lithography she then stamps the pattern onto a polymer matrix and the nanowires are grown by applying electric current through electrodeposition.
The entire structure is surrounded by a polymer matrix. Nath and her research team can produce wires of any shape or size.
The polymer which is nonconductive can be removed to allow the wires to stand freely and yet not lose shape or consistency.
The actual micro-scallop was made of a relatively hard plastic. The challenge was to make the shells extremely thin
As in the case of their plastic micro-scallop the researchers also envision medical applications for their nanosubmarine.
This crystal structure creates a more robust edge and the more edge the better for catalytic reactions
but traditionally employed to thicken natural oxide layers on metals. The film was exposed then to sulfur vapor at 300 degrees Celsius (572 degrees Fahrenheit) for one hour.
Zang and his team found a way to break up bundles of the carbon nanotubes with a polymer
"By modifying the surface of the nanotubes with a polymer, the material can be tuned to detect any of more than a dozen explosives,
#Researchers improve thermal conductivity of common plastic by adding graphene coating (Phys. org) A team of engineering
and physics researchers with members from the U s. the U k. and the Republic of Muldova has found that covering a common type of plastic with a graphene coating can increase its conductivity by up to 600 times.
Plastics are not very good conductors of heat they are generally in the 0. 15-0. 24 W/mk range
In this new effort the researchers sought to improve heat conduction in a plastic by applying graphene to its surface.
The type of plastic used PET is very common it's used to make soda bottles and a myriad of other products in a nearly limitless variety of shapes.
which are based on multiscale simulations that will shed light on which sorts of real-world applications the coated plastics might best be used in.
http://arxiv. org/ftp/arxiv/papers/1407/1407.1359. pdfabstractwe have investigated thermal conductivity of graphene laminate films deposited on polyethylene terephthalate substrates.
Coating plastic materials with thin graphene laminate films that have up to 600 higher thermal conductivity than plastics may have important practical implications s
and revealed the widespread transition from one crystal structure to another. The team also measured the amount of oxygen
depositing thin films of a uniquely designed polymer on a template so that it self-assembles into neat, precise, even rows of alternating composition just 10 or so nanometers wide.
and IBM Almaden Research center focuses on block copolymers a special class of polymers that under the proper conditions, will segregate on a microscopic scale into regularly spaced"domains"of different chemical composition.
and measure the shape and dimensions of the polymer rows in three dimensions. The experimental techniques can prove essential in verifying
Hence the polymers.""The issue in semiconductor lithography is not really making small featuresou can do thatut you can't pack them close together,
"Block copolymers take advantage of the fact that if I make small features relatively far apart, I can put the block copolymer on those guiding patterns
and sort of fill in the small details.""The strategy is called"density multiplication"and the technique,"directed self-assembly."
"Block copolymers (BCPS) are a class of materials made by connecting two or more different polymers that,
the BCPS in question will form a thin film in a pattern of narrow, alternating stripes of the two polymer compositions.
Alternatively, they can be designed so one polymer forms a pattern of posts embedded in the other.
Remove one polymer, and in theory, you have a near-perfect pattern for lines spaced 10 to 20 nanometers apart to become, perhaps, part of a transistor array.
although the basic technique was developed using short wavelength"hard"X rays that have difficulty distinguishing two closely related polymers,
***Unlike the scattering technique, the TEM tomography can actually image defects in the polymer structureut only for a small area.
because its two-dimensional structure and unique chemical properties made it a promising candidate for new applications such as energy storage material composites as well as computing
Graphene is remarkably strong for its low weight-about 100 times stronger than steel -and it conducts heat and electricity with great efficiency.
The global market for graphene is reported to have reached US$9 million this year with most sales concentrated in the semiconductor electronics battery energy and composites.
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