and enable the economic production of gas resources with higher carbon dioxide content that would be too costly to recover using current carbon capture technologies says James Tour professor of mechanical engineering and nanoengineering and of computer science at Rice university.
HOW IT WORKS When the terahertz light hits the transducer, the nanotubes absorb it, turning it into heat.
Much of Reguera research with these bacteria focuses on engineering their conductive pili or nanowires.
He and graduate student Andrew Westover have built small aferdevices in the Nanomaterials and Energy Devices Laboratory there. ndrew has managed to make our dream of structural energy storage materials into a realitysays Pint.
because they go dead. estover s wafers consist of electrodes made from silicon that have been treated chemically so they have nanoscale pores on their inner surfaces
and solidifies it forms an extremely strong mechanical bond. he biggest problem with designing load-bearing supercaps is preventing them from delaminatingsays Westover. ombining nanoporous material with the polymer electrolyte bonds the layers together tighter than superglue. he use
#DNA motor uses arms to walk across a nanotube Purdue University rightoriginal Studyposted by Emil Venere-Purdue on December 19 2013engineers made a motor out of DNA
and then used it to move nanoparticles of cadmium disulfide along the length of a nanotube.
New findings were detailed in a paper published this month in the journal Nature Nanotechnology.
As it moves along a carbon-nanotube track it continuously harvests energy from strands of RNA molecules vital to a variety of roles in living cells
and viruses. ur motors extract chemical energy from RNA molecules decorated on the nanotubes and use that energy to fuel autonomous walking along the carbon nanotube trackchoi says.
The core is made of an enzyme that cleaves off part of a strand of RNA. After cleavage the upper DNA arm moves forward binding with the next strand of RNA
The process repeats until reaching the end of the nanotube track. The researchers combined two fluorescent imaging systems to document the motor s movement one in the visible spectrum and the other in the near-infrared range.
The nanoparticle is fluorescent in visible light and the nanotubes are fluorescent in the near-infrared.
The motor took about 20 hours to reach the end of the nanotube which was several microns long
but the process might be sped up by changing temperature and ph a measure of acidity.
or the first time we predicted their properties using quantum mechanics. he nanocrystals are about 3 nanometers wide by 500 nanometers longor about 1/1000th the width of a grain of sandmaking them too small to study with light microscopes
The findings represent a milestone in understanding the fundamental mechanical behavior of the cellulose nanocrystals. t is also the first step towards a multiscale modeling approach to understand
and medical devices to structural components for the automotive civil and aerospace industries. he cellulose nanocrystals represent a potential green alternative to carbon nanotubes for reinforcing materials such as polymers and concrete.
and bacteria that create a protective web of cellulose. ith this in mind cellulose nanomaterials are inherently renewable sustainable biodegradable and carbon-neutral like the sources from
and infrastructure applications. or the future Wang and his research team plan to continue studying the nanogenerators
when (Lockheed martin engineer) Vladimir Volman saw a presentation by Yu Zhu a postdoc in my lab at the timehe says. olman had calculated that one could pass a current through a graphene film less than 100 nanometers thick
Zhu was presenting his technique for spraying nanoribbons films and Volman recognized the potential. ristine graphene transmits electricity ballistically
but graphene nanoribbons (GNRS) unzipped from multiwalled carbon nanotubes in a chemical process invented by the Tour group in 2009 do the job nicely he says.
The 100-nanometer layer of GNRSÂ##thousands of times thinner than a human hairâ##was hooked to platinum electrodes.
Tour says the availability of nanoribbons is no longer an issue now that they re being produced in industrial quantities. ow we re going to the next levelhe says noting that GNR films made into transparent films might be useful for deicing car windshields a project the lab intends to pursue.
Volman suggests the material would make a compelling competitor to recently touted nanotube-based aerogels for deicing airplanes in the winter. e have the technology;
Nanostructured metamaterials however are making it possible to reduce the wavelength of light allowing the creation of new types of nanophotonic devices says Vladimir M. Shalaev scientific director of nanophotonics at Purdue s Birck Nanotechnology Center
and professor of electrical and computer engineering. he most important thing is that we can do this with a very thin layer only 30 nanometers
Under development for about 15 years metamaterials owe their unusual potential to precision design on the scale of nanometers.
The new process described in the journal Nature Communications allows a measure of control over their size generally from 2 to 20 nanometers depending on the source of the coal.
Bituminous coal produced GQDS between 2 and 4 nanometers wide. Coke produced GQDS between 4 and 8 nanometers and anthracite made stacked structures from 18 to 40 nanometers with small round layers atop larger thinner layers.
Just to see what would happen the researchers treated graphite flakes with the same process
A small change in the size of a quantum dot as little as a fraction of a nanometer##changes its fluorescent wavelengths by a measurable factor
So this discovery can really change the quantum dot industry. It'#going to show the world that inside of coal are these very interesting structures that have real value. he Air force Office of Scientific research
and effective blockage of oil spreading. ur work is based on micro/nanoelectromechanical systems or M/NEMS
or mechanical structures that allow researchers to conduct their work on the micro/nanoscopic levelsays Jae Kwon associate professor of electrical and computer engineering at the University of Missouri. il-based materials or low-surface tension liquids
and virtual walls for low-surface tension liquids also have immense potential for many lab-on-a-chip devices
#DNA helps nanoparticle crystals self-assemble Northwestern University rightoriginal Studyposted by Megan Fellman-Northwestern on December 2 2013using the same structure found in nature researchers have built the first near-perfect single crystals
out of gold nanoparticles and DNA. ingle crystals are the backbone of many things we rely onâ##diamonds for beauty as well as industrial applications sapphires for lasers
and silicon for electronicssays nanoscientist Chad A. Mirkin. he precise placement of atoms within a well-defined lattice defines these high-quality crystals. ow we can do the same with nanomaterials
research group developed the ecipefor using nanomaterials as atoms DNA as bonds and a little heat to form tiny crystals.
Given a set of nanoparticles and a specific type of DNA Olvera de la Cruz showed they can accurately predict the 3d structure
The team worked with gold nanoparticles but the recipe can be applied to a variety of materials with potential applications in the fields of materials science photonics electronics
In the study strands of COMPLEMENTARY DNA act as bonds between disordered gold nanoparticles transforming them into an orderly crystal.
The researchers determined that the ratio of the DNA linker s length to the size of the nanoparticle is critical. f you get the right ratio it makes a perfect crystalâ##isn t that fun?
and realized experimentally. o achieve a self-assembling single crystal in the lab the research team reports taking two sets of gold nanoparticles outfitted with COMPLEMENTARY DNA
Working with approximately 1 million nanoparticles in water they heated the solution to a temperature just above the DNA linkers melting point
The researchers determined that the length of DNA connected to each gold nanoparticle can t be much longer than the size of the nanoparticle.
In the study the gold nanoparticles varied from five to 20 nanometers in diameter; for each the DNA length that led to crystal formation was about 18 base pairs and six single-base ticky ends.?
There s no reason we can t grow extraordinarily large single crystals in the future using modifications of our techniquesays Mirkin who also is a professor of medicine chemical and biological engineering biomedical engineering and materials science and engineering and director of the university s International Institute for Nanotechnology.
The combination of these properties makes graphene an ideal material for nanoelectromechanical systems (NEMS) which are scaled-down versions of the microelectromechanical systems (MEMS) used widely for sensing of vibration and acceleration.
For example Hone explains MEMS sensors figure out how your smartphone or tablet is tilted to rotate the screen.
In this new study published in Nature Nanotechnology the team took advantage of graphene s mechanical tretchabilityto tune the output frequency of their custom oscillator creating a nanomechanical version of an electronic component known as a voltage controlled oscillator (VCO.
For the battery project Chao added tiny nanoparticles of carbon to the polymer so it would conduct electricity. e found that silicon electrodes lasted 10 times longer
#Tiny Lego blocks build two-faced nanotubes University of Warwick rightoriginal Studyposted by Anna Blackaby-Warwick on November 14 2013using a process similar to molecular Lego scientists
and can be controlled with a much higher level of accuracy than natural channel proteins. hrough a process of molecular engineeringâ##a bit like molecular Legoâ##we have assembled the nanotubes from two types of building blocksâ##cyclic peptides
and polymers. anus nanotubes are a versatile platform for the design of exciting materials which have a wide range of application from membranesâ##for instance for the purification of waterâ##to therapeutic uses including the development of new drug systems. ource:
to make lithium-sulfur cathodes by synthesizing a nanocomposite consisting of sulfur coated with a common inexpensive conductive polymer called polyaniline and
However they have been catching up rapidly. he big challenge for this approach is assembling the materialssays Pint. onstructing high-performance functional devices out of nanoscale building blocks with any level of control has proven to be quite challenging
they used porous silicon a material with a controllable and well-defined nanostructure made by electrochemically etching the surface of a silicon wafer.
This allowed them to create surfaces with optimal nanostructures for supercapacitor electrodes but it left them with a major problem.
With experience in growing carbon nanostructures Pint s group decided to try to coat the porous silicon surface with carbon. e had no idea
but it was coated by a layer of graphene a few nanometers thick. They tested the coated material
which is made typically of tungsten##an abundant material also used in conventional light bulbs. ur thermal emitters have a complex three-dimensional nanostructure that has to withstand temperatures above 1800 F 1000 C to be practicalbraun says n fact the hotter
however the 3-D structure of the emitter was destroyed at temperatures of around 1800 F (1000 C). To address the problem Braun and his Illinois colleagues coated tungsten emitters in a nanolayer of a ceramic material called hafnium
#Nanoribbon material keeps gases captive Rice university rightoriginal Studyposted by Mike Williams-Rice on October 11 2013an enhanced polymer could make vehicles that run on compressed natural gas more practical and even prolong the shelf life of bottled beer
Tour s breakthrough nzippingtechnique for turning multiwalled carbon nanotubes into GNRS first revealed in Nature in 2009 has been licensed for industrial production. hese are being produced in bulk
But the overlapping 200-to 300-nanometer-wide ribbons dispersed so well that they were nearly as effective as large-sheet graphene in containing gas molecules.
and materials science and of chemistry. t a few nanometers wide they'##re a totally noninvasive coating.
The findings are published in Nature Nanotechnology. Chemists and educators teach and use chemical reaction networks a century-old language of equations that describes how mixtures of chemicals behave.
The channel had earlier been patterned with precisely spaced nanoscale ridges. Infrared laser light shining on the pattern generates electrical fields that interact with the electrons in the channel to boost their energy.
and received funding support from the Defense Advanced Research Projects Agency Caltech s Kavli Nanoscience Institute and the Institute for Quantum Information and Matter an
#Does this carbon nanotube computer spell the end for silicon? Stanford university rightoriginal Studyposted by Tom Abate-Stanford on September 27 2013engineers have built a basic computer using carbon nanotubes a success that points to a potentially faster more efficient alternative to silicon chips.
The achievement is reported in an article on the cover of the journal Nature. eople have been talking about a new era of carbon nanotube electronics moving beyond siliconsays Subhasish Mitra an electrical engineer
Here is the proof. xperts say the achievement will galvanize efforts to find successors to silicon chips which could soon encounter physical limits that might prevent them from delivering smaller faster cheaper electronic devices. arbon nanotubes CNTS have long been considered as a potential successor to the silicon transistorsays Professor
But until now it hasn t been clear that CNTS a semiconductor material could fulfill those expectations. here is no question that this will get the attention of researchers in the semiconductor community
Mihail Roco a senior advisor for nanotechnology at the National Science Foundation called the work n important scientific breakthrough. t was roughly 15 years ago that carbon nanotubes were fashioned first into transistors the on-off switches
But a bedeviling array of imperfections in these carbon nanotubes has frustrated long efforts to build complex circuits using CNTS.
team has made to this worldwide effort. irst they put in place a process for fabricating CNT-based circuitsde Micheli says. econd they built a simple
but effective circuit that shows that computation is doable using CNTS. s Mitra says: t s not just about the CNT COMPUTER.
It s about a change in directions that shows you can build something real using nanotechnologies that move beyond silicon
and its cousins. uch concerns arise from the demands that designers place upon semiconductors and their fundamental workhorse unit those on-off switches known as transistors.
He called the Stanford work major benchmarkin moving CNTS toward practical use. CNTS are long chains of carbon atoms that are extremely efficient at conducting and controlling electricity.
They are so thinâ##thousands of CNTS could fit side by side in a human hairâ##that it takes very little energy to switch them off according to Wong a co-author of the paper. hink of it as stepping on a garden hosewong explains. he thinner the hose the easier it is to shut off the flow. n theory this combination
of efficient conductivity and low-power switching make carbon nanotubes excellent candidates to serve as electronic transistors. NTS could take us at least an order of magnitude in performance beyond where you can project silicon could take uswong said.
First CNTS do not necessarily grow in neat parallel lines as chipmakers would like. Over time researchers have devised tricks to grow 99.5 percent of CNTS in straight lines.
But with billions of nanotubes on a chip even a tiny degree of misaligned tubes could cause errors
so that problem remained. A second type of imperfection has stymied also CNT technology. Depending on how the CNTS grow a fraction of these carbon nanotubes can end up behaving like metallic wires that always conduct electricity instead of acting like semiconductors that can be switched off.
Since mass production is the eventual goal researchers had to find ways to deal with misaligned
and/or metallic CNTS without having to hunt for them like needles in a haystack. e needed a way to design circuits without having to look for imperfections
or even know where they weremitra says. The Stanford paper describes a two-pronged approach that the authors call an mperfection-immune design. o eliminate the wire-like
or metallic nanotubes the Stanford team switched off all the good CNTS. Then they pumped the semiconductor circuit full of electricity.
All of that electricity concentrated in the metallic nanotubes which grew so hot that they burned up
This sophisticated technique eliminated the metallic CNTS in the circuit. Bypassing the misaligned nanotubes required even greater subtlety.
The Stanford researchers created a powerful algorithm that maps out a circuit layout that is guaranteed to work no matter
whether or where CNTS might be askew. his imperfections-immune design technique makes this discovery truly exemplarysays Sankar Basu a program director at the National Science Foundation.
Their CNT COMPUTER performed tasks such as counting and number sorting. It runs a basic operating system that allows it to swap between these processes.
In a demonstration of its potential the researchers also showed that the CNT COMPUTER could run MIPS a commercial instruction set developed in the early 1980s by then Stanford engineering professor and now university President John Hennessy.
Though it could take years to mature the Stanford approach points toward the possibility of industrial-scale production of carbon nanotube semiconductors according to Naresh Shanbhag a professor at the University of Illinois at Urbana-Champaign
and director of SONIC a consortium of next-generation chip design research. he Wong/Mitra paper demonstrates the promise of CNTS in designing complex computing systemsshanbhag says adding that this will motivate researchers elsewhere toward greater efforts in chip design
and a world leader in CNT research. The National Science Foundation SONIC the Stanford Graduate Fellowship and the Hertz Foundation Fellowship funded the work.
Using a scanning electron microscope the Stanford team captured images of these microbes attaching milky tendrils to the carbon filaments. ou can see that the microbes make nanowires to dump off their excess electronscriddle says.
#Ink-jet printing creates soft nanostructures A new way to make nanostructures combines advanced ink-jet printing technology with block copolymers that spontaneously form ultra-fine structures.
Researchers were able to increase the resolution of their intricate structure fabrication from approximately 200 nanometers to approximately 15 nanometers.
A nanometer is a billionth of a meter the width of a double-stranded DNA molecule.
The ability to fabricate nanostructures out of polymers DNA proteins and other oftmaterials has the potential to enable new classes of electronics diagnostic devices and chemical sensors.
Recently developed ultra high-resolution ink jet printing techniques have some potential with demonstrated resolution down to 100-200 nanometers
but there are significant challenges in achieving true nanoscale dimension. ur work demonstrates that processes of polymer self-assembly can provide a way around this limitationsays John Rogers professor of materials science and engineering at University of Illinois at Urbana-Champaign.
and a co-author of the paper in Nature Nanotechnology. his concept turned out to be really usefulrogers says.
For the new paper this was done at imec in Belgium an independent nanoelectronics research center. The resolution of the chemical pattern nears the current limit of traditional photolithography notes Lance Williamson a graduate student in molecular engineering at University of Chicago
And because e-jet can naturally handle fluid inks it is suited exceptionally well for patterning solution suspensions of nanotubes nanocrystals nanowires
and other types of nanomaterials. he most interesting aspect of this work is the ability to combine top down techniques of jet printing with â##bottom upâ##processes of self-assembly in a way that opens up new capabilities
in lithographyâ##applicable to soft and hard materials alikerogers says. he opportunities are in forming patterned structures of nanomaterials to enable their integration into real devices.
The nanoscale building blocks display remarkable strength and resistance to failure despite being more than 85 percent air.
of which are measured on the scale of billionths of meters or nanometers. Julia R. Greer professor of materials science and mechanics at the California Institute of technology (Caltech) says the work was inspired by earlier work to fabricate extremely lightweight microtrusses. e designed architectures with building blocks that are less than five microns
long meaning that they are not resolvable by the human eye. onstructing these architectures out of materials with nanometer dimensions has enabled us to decouple the materials strength from their density
which are very stiff yet extremely lightweight. t the nanometer scale solids have been shown to exhibit mechanical properties that differ substantially from those displayed by the same materials at larger scales.
For example Greer s group has shown previously that at the nanoscale some metals are about 50 times stronger than usual
and removed the polymer core leaving a ceramic nanolattice. The lattice is constructed of hollow struts with walls no thicker than 75 nanometers. e are now able to design exactly the structure that we want to replicate
and then process it in such a way that it s made out of almost any material class we d likeâ##for example metals ceramics
and the Kavli Nanoscience Institute at Caltech provided support and infrastructure. Source: Caltechyou are free to share this article under the Creative Commons Attribution-Noderivs 3. 0 Unported license t
researchers use nanoplasmonicsevices that use short electromagnetic waves to modulate light on the nanometer scale, where conventional optics do not work.
you really need to precisely control light in nanoscale, and that where this work can be a very important component,
and the Penn State Center for Nanoscale Science funded this study. Source: Penn Stat i
#The National Science Foundation the Gordon and Betty Moore Foundation the Air force Office of Scientific research and the Kavli Nanoscience Institute at Caltech supported the work.
They used liquid electrolytes#generally the conductor in traditional supercapacitors#to control the spacing between graphene sheets on the subnanometer scale.
##Solar steam kills germs while off the grid RICE (US) A new sterilization system uses nanomaterials to convert 80 percent of the energy in sunlight into heat,
Solar steam efficiency comes from light-harvesting nanoparticles that were created at LANP by Rice graduate student Oara Neumann,
Neumann created a version of nanoshells that converts a broad spectrum of sunlightncluding both visible and invisible bandwidthsirectly into heat.
Is nanotech toxic? Discovered about a decade ago graphene is a sheet of carbon just one atom thick.
and material scientists at Brown aimed at understanding the toxic potential of a wide variety of nanomaterials.
This is about the safe design of nanomaterials she says. Theye man-made materials so we should be able to be clever
Rice university chemist James Tour and colleagues, who developed a method for unzipping nanotubes into graphene nanoribbons (GNRS),
In the new experiments, the Rice lab mixed graphene nanoribbons and tin oxide particles about 10 nanometers wide in a slurry with a cellulose gum binder and a bit of water, spread it on a current collector
but also help deliver lithium ions to the nanoparticles. Major hurdle Lab tests showed initial charge capacities of more than 1
Tour says. raphene nanoribbons make a terrific framework that keeps the tin oxide nanoparticles dispersed and keeps them from fragmenting during cycling,
he adds. ince the tin oxide particles are only a few nanometers in size and permitted to remain that way by being dispersed on GNR surfaces,
the volume changes in the nanoparticles are not dramatic. NRS also provide a lightweight, conductive framework, with their high aspect ratios and extreme thinness.
Lin says the lab plans to build batteries with other metallic nanoparticles to test their cycling and storage capacities.
#Our nanotechnology produces entanglements that are millions of times more dense than woven products such as fabrics
At the core of the device is a nanoscale structure#about a tenth of a millimeter wide
and by patterning it with these nanoscale antennas the conversion efficiency of the detector improves 10 times.#
The National Science Foundation Penn s Materials Research Science and Engineering Center Penn s Nano/Bio Interface Center and the Penn Regional Nanotechnology Facility
Exposure to high radiation alone produces significant damage at the nanoscale, so scientists at Los alamos National Laboratory, New mexico, have been working on a mechanism that allows nanocrystalline materials to heal themselves after suffering radiation-induced damage.
This gives hope for materials that will improve the reliability, safety and lifespan of nuclear energy systems.
The nanocrystalline materials the scientists have been working on are created those from nanosized particles, in this case from copper.
Nanocrystalline materials comprise a mixture of grains and the interface between those grains, called grain boundaries.
Nanocrystalline materials contain a large amount of grain boundaries which are thought to be able to absorb
But until conducting recent computer simulations, scientists lacked the ability to predict the performance of nanocrystalline materials in extreme environments.
the researchers describe a newly discovered oading-unloadingphenomenon at grain boundaries in nanocrystalline materials, which allows for effective self-healing of radiation-induced defects.
While electrons ordinarily flow freely through the nanotubes, any ethylene molecules present in the vicinity will bond with the copper atoms,
which absorb ethylene and concentrate it near the nanotubes. By measuring how much the electron flow has been slowed,
It's these approximately 100-nanometers-wide slits that allow the device to differentiate between colors with plasmons waves of electrons that flow across metal surfaces) excited by light of a specific wavelength.
#Scientists find that exposure to nanoparticles could impact cardiovascular health Due to its huge potential in applications ranging from cheaper vaccinations to energy-storing car panels there's plenty of excitement surrounding the emergence of nanotechnology.
But a team of scientists are urging caution with a study conducted at the Technion-Israel Institute of technology suggesting that exposure to silicon-based nanoparticles may play a role in the development of cardiovascular disease.
exposing them to nanoparticles made from silicon dioxide. The team was seeking to explore the effects that the nanoparticles have on the development of atherosclerosis a condition that leads to the hardening of the arteries and cardiovascular events such as heart attack and stroke.
What the researchers found was a negative relationship between the silicon-based nanoparticles and macrophages a type of white blood cell that destroys damaged or dead cells.
The toxicity of the nanoparticles causes the macrophages to transform into foam cells or lipids leading to the development of lesions and hastening the onset of atherosclerosis.
This exposure may be especially chronic for those employed in research laboratories and in high tech industry where workers handle manufacture use
and dispose of nanoparticles says the study's lead author Professor Michael Aviram. 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
risk for consumers as well. This study isn't the first time concerns have been raised about the dangers of nanotechnology.
Operating at a scale of 1-100 nanometers (a nanometer is one billionth of a meter) the chemical reactions
when dealing with nanotechnology can be somewhat unpredictable. Previous research has turned up some unsettling results including that silver nanoparticles can materially alter a person's immunity and that titanium dioxide nanoparticles cause systemic genetic damage in mice.
The researchers warn that adopting a cautious approach is critical in the near-term with nanotechnology-based consumer products on the rise a world market they estimate will hit US$3 trillion by 2020.
This reality leads to increased human exposure and interaction of silica-based nanoparticles with biological systems write the researchers.
Because our research demonstrates a clear cardiovascular health risk associated with this trend steps need to be taken to help ensure that potential health
and environmental hazards are being addressed at the same time as the nanotechnology is being developed. The research was published in the journal Environmental Toxicology y
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