The particle growth in the diameter range between about three and one hundred nanometers requires low-volatile organic vapors as has been speculated.
which had taken not sufficiently into account the growth of nanoparticles caused by these compounds produced in boreal regions.
Scientists have known for decades that gases from pine trees can form particles that grow from just 1 nanometer in size to 100 nanometers in about a day.
and at 100 nanometers they are large enough to condense water vapor and prompt cloud formation.
and condenses onto small particles of just 3 nanometers. Researchers found so many of these molecules are produced that they can clump together
#Caps not the culprit in nanotube chirality: New study narrows possibilities for gaining control of nanotube typea single-walled carbon nanotube grows from the round cap down so it's logical to think the cap's formation determines
what follows. But according to researchers at Rice university that's not entirely so. Theoretical physicist Boris Yakobson and his Rice colleagues found through exhaustive analysis that those who wish to control the chirality of nanotubes--the characteristic that determines their electrical properties--would be wise to look at other aspects of their growth.
In the study by Yakobson research scientist Evgeni Penev and postdoctoral researcher Vasilli Artyukhov that was published recently by the American Chemical Society journal ACS Nano the Rice researchers found that the elastic energy landscapes
involved in cap formation are not strong enough to dictate the nanotube's chirality. To get a clear picture of how caps are related to nanotube chirality the Rice group embarked upon a detailed two-year census of the 4500 possible cap formations for nanotubes of just two diameters 0. 8
and 1 nanometer across 21 chiralities. The cap of every nanotube has six pentagons--none
of which may touch each other--among an array of hexagons Penev said. They pull the cap
and force it to curve but their positions are not always the same from cap to cap.
But because a given chirality can have hundreds of possible caps the determining factor for chirality must lie elsewhere the researchers found.
A nanotube is an atom-thick sheet of carbon atoms arranged in hexagons and rolled into a tube.
and that angle controls how well the nanotube will conduct electricity. A perfect conducting metallic nanotube would have arranged the atoms in armchairs so-called
because cutting the nanotube in half would make the top look like a series of wells with atoms for armrests.
Turn the hexagons 30 degrees though will make a semiconducting zigzag nanotube. Nanotubes can be one
or the other or the chiral angle can be anything in between with a shifting range of electrical properties.
Getting control of these properties has been a struggle. Ideally scientists could grow the specific kinds of nanotubes they need for an application
but in reality they grow as a random assortment that must then be separated with a centrifuge or by other means.
Yakobson suspects the answer lies in tuning the interaction between the catalyst and the nanotube edge.
Yakobson is Rice's Karl F. Hasselmann Professor of Mechanical engineering and Materials Science a professor of chemistry and a member of the Richard E. Smalley Institute for Nanoscale Science and Technology.
#New pomegranate-inspired design solves problems for lithium-ion batteriesan electrode designed like a pomegranate--with silicon nanoparticles clustered like seeds in a tough carbon rind--overcomes several remaining
and SLAC who led the research reported today in Nature Nanotechnology. Experiments showed our pomegranate-inspired anode operates at 97 percent capacity even after 1000 cycles of charging
Over the past eight years Cui's team has tackled the breakage problem by using silicon nanowires
or nanoparticles that are too small to break into even smaller bits and encasing the nanoparticles in carbon yolk shells that give them room to swell
and shrink during charging. The new study builds on that work. Graduate student Nian Liu and postdoctoral researcher Zhenda Lu used a microemulsion technique common in the oil paint
and find a cheaper source of silicon nanoparticles. One possible source is rice husks: They're unfit for human food produced by the millions of tons and 20 percent silicon dioxide by weight.
According to Liu they could be transformed into pure silicon nanoparticles relatively easily as his team recently described in Scientific Reports.
#Carbon nanotube fibers outperform copper in carrying electrical currenton a pound-per-pound basis carbon nanotube-based fibers invented at Rice university have greater capacity to carry electrical current
While individual nanotubes are capable of transmitting nearly 1000 times more current than copper the same tubes coalesced into a fiber using other technologies fail long before reaching that capacity.
But a series of tests at Rice showed the wet-spun carbon nanotube fiber still handily beat copper carrying up to four times as much current as a copper wire of the same mass.
Scanning electron microscope images show typical carbon nanotube fibers created at Rice university and broken into two by high-current-induced Joule heating.
Kono Lab/Rice university) That said the researchers makes nanotube-based cables an ideal platform for lightweight power transmission in systems where weight is a significant factor like aerospace applications.
Just a year ago the journal Science reported that Pasquali's lab in collaboration with scientists at the Dutch firm Teijin Aramid created a very strong conductive fiber out of carbon nanotubes.
Scientists working with nanoscale materials have thought long there's a better way to move electricity from here to there.
Certain types of carbon nanotubes can carry far more electricity than copper. The ideal cable would be made of long metallic armchair nanotubes that would transmit current over great distances with negligible loss
but such a cable is not feasible because it's not yet possible to manufacture pure armchairs in bulk Pasquali said.
In the meantime the Pasquali lab has created a method to spin fiber from a mix of nanotube types that still outperforms copper.
and materials scientists working on carbon nanotubes. That has generated some confusion in the literature over the right comparisons to make he said.
The researchers found nanotube fibers exposed to nitrogen performed best followed by argon and open air all of
The same nanotube fibers in a vacuum could only cool by radiation and had the lowest CCC.
and computer engineering of physics and astronomy and of materials science and nanoengineering. Pasquali is a professor of chemical and biomolecular engineering chemistry and materials science and nanoengineering.
Tsentalovich Kono and Pasquali are members of the Richard E. Smalley Institute for Nanoscale Science and Technology.
The research was supported by the Department of energy the National Science Foundation the Robert A. Welch Foundation Teijin Aramid BV the Air force Office of Scientific research and the Department of defense National Defense Science and Engineering Graduate Fellowship.
Plasmon-generated electrons timed moving from nanorods to grapheneplasmonic nanoparticles developed at Rice university are becoming known for their ability to turn light into heat
They suggest that the extraction of electrons generated by surface plasmons in metal nanoparticles may be optimized.
The work was reported recently in the American Chemical Society journal ACS Nano. We've looked at this process on a single-particle level said lead author Hoggard.
Dark-field scattering and photoluminescence spectroscopy of more than 200 nanoparticles helped them determine that it takes about 160 femtoseconds (quadrillionths of a second) for an electron to transfer from the particle to highly conducting graphene the single-atom-thick form of carbon.
but how fast usable electrons flow from plasmonic nanoparticles is understood little. The plasmon generates hot electrons that decay very quickly so intercepting them is a challenge he said.
That thought prompted Link's lab to embark upon the painstaking effort to analyze single nanoparticles.
and the shape of the nanoparticle Hoggard said. And it usually appears as a single peak for gold nanorods.
when nanoparticles are introduced into an electron-accepting environment which in this case is graphene. The Rice lab hopes to optimize the connection between the nanoparticles
and graphene or another substrate preferentially a semiconductor that will allow them to trap hot electrons.
Science and Nanoengineering. Link is an associate professor of chemistry and of electrical and computer engineering.
The researchers reported their work yesterday in Nature Nanotechnology. Water evaporation is the largest power source in nature Sahin said.
-and nanostructured photoelectric devices as well as for semiconductor layers consisting of other materials says Mainz. But we continue to focus on kesterites
when a buckyball attaches to a gold surface in the optical nano antenna used to measure the effects of an electric current on intermolecular bonds through a technique called Raman spectroscopy.
Natelson's group built the nano antenna a few years ago to trap small numbers of molecules in a nanoscale gap between gold electrodes.
The nano antenna is able to detect the tone of detuned vibrations between atoms through surface-enhanced Raman spectroscopy (SERS) a technique that improves the readings from molecules
The discovery of buckyballs which earned a Nobel prize for two Rice professors kick-started the nanotechnology revolution.
and Molecular Foundry director Jeffrey Neaton a professor of physics at the University of California Berkeley and a member of the Kavli Energy Nanosciences Institute at Berkeley.
Apple bakes fitness deeper into its ipod nano device with Nike+Ten years after its debut, Apple is integrating fitness more deeply into its line of ipods.
On Tuesday, Apple announced that its seventh generation ipod nano will allow people to track their activity with Nike+.
The newest ipod nano has a square screen that can double as a watch. The difference is that it can hook up with the Nike+via an embedded receiver that's been baked into the device.
but Agrisolar relies on wavelengths between 361 and 368 nanometers. The company which is headquartered in Colorado
This morning we're reading about nanotechnology. 1.)From pomegranate peel to nanoparticles. Food waste is a growing problem in many parts of the world,
but discarded fruit peel, in the case of pomegranates, could be put to good use in the burgeoning field of nanotechnology according to research published in the International Journal of Nanoparticles. 2.)U s. Government Accountability Office
releases report on nanotechnology EHS research performance. From fiscal years 2006 to 2010, the National Science and Technology Council (NSTC) reported more than a doubling of National Nanotechnology Initiative (NNI) member agencies'funding for nanotechnology environmental
health, and safety (EHS) research. 3.)Nanotech innovations bring breakthroughs to market. The operators of a local scientific supply business hope they can help researchers find breakthrough developments in tiny tubes. 4.)Nanotechnology in the automotive industry.
Nano-enhanced materials are already beginning to improve the performance and cost-effectiveness of vehicles,
and this effect will only increase in the coming years, as harder, stronger, lighter nanomaterials become commercially available. 5.)Chemist explores nanotechnology in search of cheaper solar cells.
Luke Hanley is a big believer in harnessing solar energy to produce electricity. Doing it more efficiently is his goal.
Bonus: U s. companies account for more than half of nanotechnology IP. Image credit: Zdenko Zivkovic Related: Could fireflies replace LED lighting?
Dressed to kill, one atom at a time Nanotubes development could double battery life Nano-advances behind new architectural products Scientists create functioning transistor from a single atom
The revolution will be bottom-uphow will we respond to the Great Contraction? Are our leaders ready to provide solutions from the top down,
which made its name from the launch of the Nano compact, the world's cheapest car,
 The team recently reported their findings in the Nanoscale. Hydrogen fuel is considered a clean fuel
These nanostructures, like the name suggests, are tiny. One of these nanowire trees can reach up to a couple of microns in length.
the nanoparticles coalesced into tiny grains comprising numerous nanotwin domains. The resulting transparent lumps of cubic boron nitride (pictured) were riddled with nanotwin segments that are just 3. 8 nanometers thick on average.
Previous attempts have managed to reduce grain sizes to 14 nanometers. Those samples had measured a hardness of up to 108 gigapascals.
That s slightly harder than synthetic diamond but less hard than polycrystalline diamonds that are made of nanoscale grains.
The work was published in Nature today. Via Scientific American Image from Tian et al.
New system predicts most influential people on Twitterrepresentative Anthony Weiner (D-New york) needs to know about rumor centrality.
MIT researchers created a carbon nanotube with a bee venom-based sensor, designed to detect traces of explosives.
The kitchen nano gardennothing can be as frustrating as loitering and searching for fresh vegetables from the market.
the new Kitchen Nano Garden serves as an excellent way to grow fresh vegetables right in your kitchen, without the use of pesticides or fertilizers.
Just place the Kitchen Nano Garden beside the Kitchen counter and grow your favorite vegetables, herbs and flowers without any hassle.
Nano Garden employs LED lighting that promotes plant growth, without the need of sunlight. The water used
vibrations in the surrounding environment derived from the piezoelectric phenomenon could provide power for future nanoscale devices.
In the future, nanodevices could use zinc oxide nanowires that draw energy from vibrations such as from the flow of blood
Dr. Robert Freitas, author of the Nanomedicine series and senior research fellow at the Institute for Molecular Manufacturing, has described several potential food replacement technologies that are somewhat pill-like.
In the January-February 2010 issue of THE FUTURIST magazine, Freitas lays out his ideas for improving human health through nanotechnology. 2. Better Design.
according to results to be published in an upcoming issue of the Institute of Electrical and Electronics Engineers'Transactions on Nanotechnology (PDF).
The UW circuit is built from parts measuring 130 nanometers and it consumes on average just 10 nanowatts of power during operation (a nanowatt is one billionth of a watt)."
But the nanoscale is not just in size, but also in the energy and power consumption,"Parviz said."
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