#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.
First author Chanyuan Liu a graduate student in materials science & engineering says that it can be charged fully in 12 minutes
Gary Rubloff director of the Maryland Nanocenter and a professor in the Department of Materials science and engineering and in the Institute for Systems Research;
Sang Bok Lee a professor in the Department of chemistry and Biochemisty and the Department of Materials science and engineering;
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.
To increase the nanowires'surface area Nath can make them hollow in the middle much like carbon nanotubes found in optics and electronics.
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.
Lee and Alex Zettl, a physicist who holds joint appointments with Berkeley Lab's Materials sciences Division
In a study led by Xiang Zhang director of Berkeley Lab's Materials sciences Division he and his research group at the University of California (UC) Berkeley achieved symmetry-breaking in a bulk metamaterial solution for the first time.
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.
Carbon nanotubes are known for their strength and high electrical conductivity and are used in products from baseball bats and other sports equipment to lithium-ion batteries and touchscreen computer displays.
and produce the first commercial scanners early next year, says cofounder Ling Zang, a professor of materials science and engineering and senior author of a study of the technology published online Nov 4 in the journal
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.
Thermal conductivity of Graphene Laminate Nano Lett. 2014 14 (9) pp 5155-5161. DOI: 10.1021/nl501996v.
http://arxiv. org/ftp/arxiv/papers/1407/1407.1359. pdfabstractwe have investigated thermal conductivity of graphene laminate films deposited on polyethylene terephthalate substrates.
and a set of suspended samples with the graphene laminate thickness from 9 to 44 m. The thermal conductivity of graphene laminate was found to be in the range from 40 to 90 W/mk at room temperature.
The thermal conductivity scales up linearly with the average graphene flake size in both uncompressed and compressed laminates.
The compressed laminates have higher thermal conductivity for the same average flake size owing to better flake alignment.
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
and carbon dioxide released by the NCA sample a key indicator of potential flammability. The oxygen release peaked between 300 and 400 degrees Celsius during our trials
This interfacial layer is critical to our understanding of a diverse set of phenomena from biology to materials science.
Miquel Salmeron a senior scientist in Berkeley Lab's Materials sciences Division (MSD) and professor in UC Berkeley's Materials science and engineering Department explains this in the context of a battery.
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.
and patented a nanofluid improving thermal conductivity at temperatures up to 400°C without assuming an increase in costs
and it offers enhanced thermal conductivity properties (an increase of up to 30%)of existing heat transfer fluids.
One characteristic that is common to all of them, according to Juliá, is"their low thermal conductivity, which is what limits the efficiency of the heat exchange systems that use them.
and increases the thermal conductivity by adding an exact proportion of nanoparticles consisting on carbon and other additives to the base fluid (diphenyl/diphenyl oxide),
it becomes possible to obtain increases of up to 30%in the thermal conductivity of the base fluid.
however because conventional metal electrode technologies are too thick(>500 nm) to be transparent to light making them incompatible with many optical approaches.
The new device uses graphene a recently discovered form of carbon on a flexible plastic backing that conforms to the shape of tissue.
Moreover graphene is nontoxic to biological systems an improvement over previous research into transparent electrical contacts that are much thicker rigid difficult to manufacture and reliant on potentially toxic metal alloys.
Hersam a professor of materials science engineering chemistry and medicine at Northwestern University has developed a method to separate nanomaterials by size
The National Science Foundation (NSF)- funded scientist theorized correctly that he could adapt it to separate carbon nanotubes rolled sheets of graphene (a single atomic layer of hexagonally bonded carbon atoms) long recognized for their potential applications in computers
The carbon nanotubes separation process which Hersam developed begins with a centrifuge tube. Into that we load a water based solution and introduce an additive
We then load the carbon nanotubes and put it into the centrifuge which drives the nanotubes through the gradient.
Carbon nanotubes are highly resilient Hersam says. That allows us to integrate electronics on flexible substrates like clothing shoes and wrist bands for real time monitoring of biomedical diagnostics and athletic performance.
Kuzum emphasizes that the transparent graphene microelectrode technology was achieved through an interdisciplinary effort of CNT and the departments of Neuroscience Pediatrics and Materials science at Penn and the division of Neurology at CHOP.
Ertugrul Cubukcu's lab at Materials science and engineering Department helped with the graphene processing technology used in fabricating flexible transparent neural electrodes as well as performing optical and materials characterization in collaboration with Euijae Shim and Jason Reed.
To overcome this challenge the researchers from the Institute for Integrated Cell-Material Sciences (icems) at Kyoto University borrowed a principle from polymer chemistry
By putting graphene oxide (an oxidized form of graphene) into contact with an oppositely charged polymer the two components could form a stable composite layer a process also known as interfacial complexation.
Interestingly the polymer could continuously diffuse through the interface and induce additional reactions which allowed the graphene-based composite to develop into thick multilayered structures.
Hence we named this process'diffusion driven layer-by-layer assembly'explained Jianli Zou a co-investigator in the project.
"said Ragan, associate professor of chemical engineering & materials science and principal investigator on the project. This grant highlights the strength of our faculty in both nanosciences
Brighter new energy saving flat panel lights based on carbon nanotubes Even as the 2014 Nobel prize in Physics has enshrined light emitting diodes (LEDS) as the single most significant and disruptive energy-efficient lighting solution of today scientists
Electronics based on carbon especially carbon nanotubes (CNTS) are emerging as successors to silicon for making semiconductor materials.
Scientists from Tohoku University in Japan have developed a new type of energy-efficient flat light source based on carbon nanotubes with very low power consumption of around 0. 1 Watt for every hour's operation
The new devices have luminescence systems that function more like cathode ray tubes with carbon nanotubes acting as cathodes
In recent years carbon nanotubes have emerged as a promising material of electron field emitters owing to their nanoscale needle shape and extraordinary properties of chemical stability thermal conductivity and mechanical strength.
Many researchers have attempted to construct light sources with carbon nanotubes as field emitter Shimoi said. But nobody has developed an equivalent and simpler lighting device.
and genetic diseases by combining the chemical specificity of the DNA with the signal readout of the metal.
The system is built around a polyethylene-glycol-based polymer that carries a small peptide component that allows it to bind preferentially to specific cell types The polymer itself serves as a photosensitizer that can be stimulated by light to release reactive oxygen species (ROS.
The natural fluorescence of the polymer assists with diagnosis and monitoring of therapy as it shows where nanoparticles have accumulated.
The ROS additionally break the link between the polymer and the doxorubicin. Thus cancer cells can be subjected to a two-pronged attack from the ROS therapy
Surface tension wicks the fluid up the side of the emitters to the tip of the cone whose narrowness concentrates the electrostatic field.
But in the new work they instead used carbon nanotubes atom-thick sheets of carbon rolled into cylinders grown on the slopes of the emitters like trees on a mountainside.
their crystal structure is influenced not by the process. The UT scientists present their#findings in the journal Advanced Functional Materials.
Within the group Inorganic Materials science UT scientists have gained a lot of experience with these materials: earlier the group developed the Pulsed laser deposition technique (PLD)# for this building the materials one atomic layer at a time.
because other patterning techniques have the risk of damaging the crystal structure and orientation and thus influence the properties of the material.
and consists of PDMS#a rubber like polymer with silicon in it. Via this mask a pattern of zinc oxide can be placed on the perovskite for example.
Using PLD a sandwich of different materials can be made. The properties of each layer are secured.
They are also suitable for fundamental research in physics and materials science. Research has been done within the Inorganic Materials science group part of the MESA+Institute for Nanotechnology at the University of Twente.
The paper'Patterning of epitaxial perovskites from micro and nano molded stencil masks'by Maarten Nijland Antony George Sean Thomas Evert Houwman Jing Xia Dave Blank Guus Rijnders Gertjan Koster
Kim tried adding different polymers to his nanosheets to make them responsive. For this experiment he incorporated a relatively simple polymer that responds to ph. He found that the resulting nanosheet would always curl in basic high ph conditions
and always flatten in acidic low ph conditions. Kim also made his nanosheets responsive to near-infrared light a wavelength of light that is harmless to humans.
creating a responsive nanosheet is just a matter of adding the right polymer. A nanosheet is like pizza dough Kim said.
A nanosheet with a heat-sensitive polymer could burn surrounding tumors to destroy them functioning as a kind of super-specific chemotherapy.
There are tons of smart polymers and metals Kim said explaining the many properties he hopes to incorporate into nanotechnology.
This new structure is composite which means it allows us to mix all different kinds of components.
Smart Composite Nanosheets with Adaptive Optical Properties Jeong-Hwan Kim Murtaza Bohra Vidyadhar Singh Cathal Cassidy and Mukhles Sowwan Applied materials & Interfaces2014.
The best carbon nanotubes (CNTS) have demonstrated conductivities far beyond those of the best metals. Thus future windings made of CNTS may have a double conductivity compared with the present-day copper windings.
which has the second best conductivity of metals at room temperature. Despite the high conductivity of copper a large proportion of the electrical machine losses occur in the copper windings.
Carbon nanotubes are rapidly becoming more common because of their usefulness in nanoelectric devices composite materials and biomedicine.
and the animals that eat them Previous research has shown that carbon nanotubes take a long time to degrade through natural processes
whether or not these pollutants can be stripped away from the carbon nanotubes by these animals'digestive systems after being ingested continued Ferguson.
Biodistribution of carbon nanotubes in the body More information: Fate of single walled carbon nanotubes in wetland ecosystems. Schierz A. Espinasse B. Wiesner M. R. Bisesi J. H. Sabo-Attwood T. Ferguson P. L. Environmental science:
a professor of materials science and engineering at Illinois."Our current understanding of nanoscale thermal transport isn't nuanced enough to quantitatively predict
"Our study focused on a variety of crystals that have controlled differences in thermal transport properties, such as Si, doped Si,
and Sige alloys,"Wilson said.""We coated these crystals with a thin metal film, heated the surface with a laser beam,
and then recorded the temperature evolution of the sample.""On length-scales shorter than the phonon mean-free-paths of the crystal,
heat is transported ballistically, not diffusively. Interfaces between materials further complicate the heat-transfer problem by adding additional thermal resistance."
when the radius of the laser beam used to heat the metal coated crystals was above ten microns,
predicts that a cubic crystal like silicon will carry heat equally well in all directions.
In particularly for crystals with defects, the boundary resistance is distributed and strongly dependent on the defect concentration."
has taken a major step in developing long-sought polymer architecture to boost power-conversion efficiency of light to electricity for use in electronic devices.
but it also solves some instability problems where the materials in mixed blends of polymers tend to lose their phase-separated behavior over time degrading energy transfer the polymer chemist says.
and packing at electrode surfaces the team combined knowledge about graphene and organic crystals. Though it was difficult Briseno says they managed to get the necessary compounds to stack like coins.
when an undergraduate chose the wrong substrate to grow crystals on. For over a week the student was growing vertical crystals
and we didn't even realize until we imaged the surface of the substrate with a scanning electron microscope.
We were shocked to see little crystals standing upright! We ultimately optimized the conditions and determined the mechanism of crystallization the polymer chemist adds.
Vertical nanopillars are ideal geometries for getting around these challenges Briseno says because charge separation/collection is most efficient perpendicular to the plastic device.
Dr. Tal Dvir and his graduate student Michal Shevach of TAU's Department of Biotechnology, Department of Materials science and engineering,
The exceptional strength of carbon nanotubes prevents the cathode from being destroyed. Traditionally accelerator scientists use lasers to strike cathodes
#Nanoengineering enhances charge transport promises more efficient future solar cells Solar cells based on semiconducting composite plastics and carbon nanotubes is one of the most promising novel technology for producing inexpensive printed solar cells.
Physicists at Umeå University have discovered that one can reduce the number of carbon nanotubes in the device by more than 100 times
while maintaining exceptional ability to transport charges. This is achieved thanks to clever nanoengineering of the active layer inside the device.
Carbon nanotubes are more and more attractive for use in solar cells as a replacement for silicon. They can be mixed in a semiconducting polymer
and deposited from solution by simple and inexpensive methods to form thin and flexible solar cells.
if carbon nanotubes are connected to each other in a controlled manner to form complex nanosized networks, one can achieve significantly higher charge transport
Previous studies have reported that there is a percolation threshold for the amount of carbon nanotubes necessary to transport efficiently electric charges in a device.
In this new study, Dr. Barbero and his team at Umeå University show that this threshold can be reduced by more than 100 times in a semiconducting polymer
The pioneering work will feature on a forthcoming cover of materials science journal Advanced Functional Materials (11 november.
Earlier lab demonstrations of similar systems could only produce devices a few centimeters on a side with expensive metal substrates so were not suitable for scaling up to commercial production he says.
While the team has demonstrated working devices using a formulation that includes a relatively expensive metal ruthenium we're very flexible about materials Chou says.
In theory you could use any metal that can survive these high temperatures. This work shows the potential of both photonic engineering
and materials science to advance solar energy harvesting says Paul Braun a professor of materials science and engineering at the University of Illinois at Urbana-Champaign who was involved not in this research.
The group is now working to optimize the system with alternative metals. Chou expects the system could be developed into a commercially viable product within five years.
Researchers from the University of Surrey and AMBER the materials science centre based at Trinity college Dublin have demonstrated now how graphene-treated nanowires can be used to produce flexible touchscreens at a fraction of the current cost.
Molybdenum disulfide is a member of a family of materials known as transition metal dichalcogenides which are currently the focus of intense research because of the unusual electronic properties they display
Okuno and his colleagues fabricated silicon nanowire arrays by metal-assisted chemical etching an approach that is simple and cost-effective.
Another potential application comes from the fact that silicon crystals at dimensions of 5 nanometers
#Self-organized indium arsenide quantum dots for solar cells Kouichi Yamaguchi is recognized internationally for his pioneering research on the fabrication and applications of'semiconducting quantum dots'(QDS.
and highly uniform quantum dots explains Yamaguchi. Our'bottom-up'approach yields much better results than the conventional photolithographic
Novel applications of'quantum dots'including lasers biological markers qubits for quantum computing and photovoltaic devices arise from the unique optoelectronic properties of the QDS
Resonant energy transfer from quantum dots to graphene More information: Edes Saputra Jun Ohta Naoki Kakuda and Koichi Yamaguchi Self-Formation of In-Plane Ultrahigh-Density Inas Quantum dots on Gaassb/Gaas (001) Appl.
Phys. Express 5 125502 (2012. DOI: dx. doi. org/10.1143/APEX. 5. 125502 Katsuyoshi Sakamoto Yasunori Kondo Keisuke Uchida and Koichi Yamaguchi Quantum dot density dependence of power conversion
Guo's team drilled hundreds of 1-millimeter-diameter holes into the surface of a thin sheet of an aluminum alloy.
Placing the nanoparticles in the sheet prior to the friction stir processing step significantly increased the concentration of nanoparticles in the composite.
or crystals of the aluminum matrix that recrystallized after being plasticized were extremely small; smaller aluminum matrix grains can flow past each other more smoothly than larger particles enhancing the strength of the material.
The best nanoparticle distribution and smallest aluminum alloy grains were obtained after passing the rotating tool through the sheet four times.
The team then demonstrated that the composite made in this way had improved significantly hardness and tensile strength compared to untreated aluminum alloy sheets.
We plan to continue this research to further improve the mechanical and thermal properties as well as the wear resistance of the nanocomposites says Guo.
Materials science and engineering: A 602 143 149 (2014) dx. doi. org/10.1016/j. msea. 2014.02.02 2
#Gold nanoparticles linked to single stranded-dna DNA create a simple but versatile genetic testing kit Tests for identifying genetic variations among individuals
#Researchers uncover properties in nanocomposite oxide ceramics for reactor fuel Nanocomposite oxide ceramics have potential uses as ferroelectrics fast ion conductors
A composite is a material containing grains or chunks of several different materials. In a nanocomposite the size of each of these grains is on the order of nanometers roughly 1000 times smaller than the width of a human hair.
In the context of nuclear energy composites have been proposed for the fuel itself as a way for example to improve the basic properties of the material such as the thermal conductivity.
It is the thermal conductivity that dictates how efficiently energy can be extracted from the fuel. Composites have also been created to store the by-products of the nuclear energy cycle nuclear waste where the different components of the composite can each store a different part of the waste.
However composites have much broader applications. The interfaces provide regions of unique electronic and ionic properties
and have been studied for enhance conductivity for applications related to batteries and fuel cells. Using simulations that explicitly account for the position of each atom within the material the Los alamos research team examined the interface between Srtio3
#Experts create unique nanoparticles for aerospace industry A development of three universities enables improved thermal and electronic properties on devices with nickel-titanium alloys.
Federal Universities of Pernambuco and Campina Grande, both in Brazil, were responsible for obtaining physical media for the shape memory titanium-nickel metal alloy (with the ability to return to its original state after being deformed.
Manufacturing methods of the alloys are very specific, so the Brazilian universities obtained them by vacuum melting the titanium to make it react with oxygen.
Then nanoparticles were obtained by thermal evaporation techniques where the molecular bonds of the metals degraded as a powder
another goal of this proyect is to train high level human resources in the areas of metallurgy alloys with shape memory,
very low electrical resistance high thermal conductivity and mechanically stretchable yet harder than diamond. Now ORC researchers have developed molybdenum di-sulphide (Mos2) a similar material to graphene that shares many of its properties including extraordinary electronic conduction
and mechanical strength but made from a metal (in this case molybdenum combined with sulphur). This new class of thin metal/sulphide materials known as transition metal di-chalcogenides (TMDCS) has become an exciting complimentary material to graphene.
However unlike graphene TMDCS can also emit light allowing applications such as photodetectors and light emitting devices to be manufactured.
#Nanotubes help healing hearts keep the beat (Phys. org) Carbon nanotubes serve as bridges that allow electrical signals to pass unhindered through new pediatric heart-defect patches invented at Rice university and Texas Children's Hospital.
The patch is attached to a polymer backbone that can hold a stitch and keep it in place to cover a hole in the heart.
Because the toxicity of carbon nanotubes in biological applications remains an open question Pasquali said the fewer one uses the better.
Instead they grew graphene onto a silicon carbide substrate under extremely high temperatures and low pressure to form the basis of the biosensor.
which are made with gold and other precious metals. The second-generation technology could allow people to use noninvasive methods to test their glucose levels through saliva tears or urine.
and polyurethane paint to melt ice on sensitive military radar domes which need to be kept clear of ice to keep them at peak performance.
but can be used to coat glass and plastic as well as radar domes and antennas. In the previous process the nanoribbons were mixed with polyurethane
but testing showed the graphene nanoribbons themselves formed an active network when applied directly to a surface.
They were coated subsequently with a thin layer of polyurethane for protection. Samples were spread onto glass slides that were iced then.
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