Nanotube

Boron nitride nanotube (11)
Carbon nanotube (525)
Metallic nanotube (5)
Nanotube (302)
Nanotube transistor (7)
Semiconducting nanotubes (6)

Synopsis: Nanotechnology: Nanostructures: Nanotube: Nanotube:

#Nanotubes: Can we make speakers as thin as paper? It's time for one of those imagined futures

so that when it is heated by the attached layer of nanotubes, it lows ith light whose peak intensity is mostly above the bandgap of the adjacent PV,

and nanotubes By injecting carbon nanotubes into the bloodstream, scientists can use near-infrared lasers to see blood flow in a living animal brain.

The light causes the specially designed nanotubes to fluoresce at wavelengths of 1, 300-1, 400 nanometers;

The fluorescing nanotubes can then be detected to visualize the blood vesselsstructure. Amazingly, the technique allows scientists to view about three millimeters underneath the scalp

but those have focused mainly on the use of one or a bundle of nanotubes. The problem LÃNARD says is that terahertz radiation typically requires an antenna to achieve coupling into a single nanotube due to the relatively large size of terahertz waves.

The researchers however found a way to create a small detector that is visible to the naked eye.

Star and his team have developed similar chip/nanotube sensors that can be affixed to a toothbrush to detect bad breath (the presence of hydrogen sulfide)

#New nanothreads are like diamond necklaces Scientists say super-thin iamond nanothreadsould be stronger and stiffer than the strongest nanotubes

The tricky bit according to Rice university chemist Angel Martã is keeping the densely packed nanotubes apart before they re drawn together into a fiber.

Earlier research at Rice by chemist and chemical engineer Matteo Pasquali a coauthor of the new paper used an acid dissolution process to keep the nanotubes separated until they could be spun into fibers.

otherwise dampen the nanotubes ability to repel one another. Put enough nanotubes into such a solution and they re caught between the repellant forces

and an inability to move in a crowded environment Martã says. They re forced to align a defining property of liquid crystals

and tightly binds the nanotubes together says Martã an assistant professor of chemistry and bioengineering and of materials science and nanoengineering.

But to make macroscopic materials Martã s team needed to pack many more nanotubes into the solution than in previous experiments. s you start increasing the concentration the number of nanotubes in the liquid crystalline phase becomes more abundant than those in the isotropic (disordered) phase

The researchers discovered that 40 milligrams of nanotubes per milliliter gave them a thick gel after mixing at high speed

and filtering out whatever large clumps remained. t s like a centrifuge together with a rotary drummartã says of the mixing gear. t produces unconventional forces in the solution. eeding this dense nanotube gel through a narrow needle-like opening produced

and the team is investigating ways to improve their electrical properties through doping the nanotubes with iodide. he research is basically analogous to

because the setup is sealed. he nanotube electrolyte solution could be protected from oxygen and water which would have caused precipitation of the nanotubeshe says. t turns out that this is not a showstopper

because we want the nanotubes to precipitate and stick to each other as soon as they exit the sealed system through the needle.

and nanotubes Stanford university rightoriginal Studyposted by Bjorn Carey-Stanford on August 7 2014by injecting carbon nanotubes into the bloodstream scientists can use near-infrared lasers to see blood flow in a living animal s brain.

The light causes the specially designed nanotubes to fluoresce at wavelengths of 1300-1400 nanometers;

The fluorescing nanotubes can then be detected to visualize the blood vessels structure. Amazingly the technique allows scientists to view about three millimeters underneath the scalp

HOW IT WORKS When the terahertz light hits the transducer, the nanotubes absorb it, turning it into heat.

#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.

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 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.

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.

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;

#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:

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 with billions of nanotubes on a chip even a tiny degree of misaligned tubes could cause errors

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

And because e-jet can naturally handle fluid inks it is suited exceptionally well for patterning solution suspensions of nanotubes nanocrystals nanowires

Rice university chemist James Tour and colleagues, who developed a method for unzipping nanotubes into graphene nanoribbons (GNRS),

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,

But the sensors aren just useful for explosives the researchers found that the coated nanotubes can also detect two pesticides that contain nitro-aromatic compounds.

Of course, duplicating synapse firings in nanotube circuits does not mean that scientists are ready to replace the human brain,

who leads the company s nanotube project at the company s T. J. Watson research center in Yorktown Heights,

New york. Nanotubes are the only technology that looks capable of keeping the advance of computer power from slowing down,

Hannon led IBM s nanotube work before Haensch, who took over in 2011 after a career working on manufacturing conventional chips.

This is the point IBM hopes nanotubes can step in. The most recent report from the microchip industry group the ITRS says the so-called five-nanometernode is due in 2019.

IBM s chosen design uses six nanotubes lined up in parallel to make a single transistor.

Each nanotube is 1. 4 nanometers wide about 30 nanometers long, and spaced roughly eight nanometers apart from its neighbors.

but so far it hasn t found a way to position the nanotubes closely enough together,

and nanotubes with compounds that would cause them to self-assemble into position. Those compounds could then be stripped away,

leaving the nanotubes arranged correctly and ready to have electrodes and other circuitry added to finish a chip.

Haensch s team buys nanotubes in bulk from industrial suppliers and filters out the tubes with the right properties for transistors using a modified version of a machine used to filter molecules such as proteins in the pharmaceutical industry.

says However, for now IBM s nanotube effort remains within its research labs, not its semiconductor business unit.

If nanotubes don t make it, there s little else that shows much potential to take over from silicon transistors in that time frame.

Our electronic whiskers consist of high-aspect-ratio elastic fibers coated with conductive composite films of nanotubes and nanoparticles.

The nanotubes provide both flexibility allowing the whiskers to bend when they experience pressure and conductivity allowing them to transmit data on the environmental factors they experience.

and height of the nanotubes the researchers were able to achieve a fluid flow that enabled an operating ion current at very near the theoretical limit.

To control the nanotubes growth the researchers first cover the emitter array with an ultrathin catalyst film

The nanotubes grow up under the catalyst particles which sit atop them until the catalyst degrades.

Using their nanotube forest they re able to get the devices to operate in pure ion mode

photosynthetic activity measured by the rate of electron flow through the thylakoid membranes was 49 percent greater than that in isolated chloroplasts without embedded nanotubes.

the nanotubes moved into the chloroplast and boosted photosynthetic electron flow by about 30 percent.

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,

In the past, researchers have exploited this phenomenon to create sensors by coating the nanotubes with molecules, such as natural antibodies, that bind to a particular target.

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,

These loops form a new layer surrounding the nanotube, known as a corona. The MIT researchers found that the loops within the corona are arranged very precisely along the tube,

and the polymer before it attaches to the nanotube. he idea is that a chemist could not look at the polymer

It has to adsorb onto the nanotube and then, by having certain sections of the polymer exposed,

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,

Researchers have struggled also to control the placement and alignment of nanotubes. Until now these two challenges have limited the development of high-performance carbon nanotube transistors.

Previous techniques to align the nanotubes resulted in less than-desirable packing density, or how close the nanotubes are to one another

when they are assembled in a film. However, the UW-Madison researchers pioneered a new technique,

#Scientists use'smallest possible diamonds'to form ultra-thin nanothreads For the first time scientists have discovered how to produce ultra-thin diamond nanothreads that promise extraordinary properties including strength and stiffness greater than that of today's strongest nanotubes

Scientists create multifunctional nanotubes using nontoxic materials A doctoral student in materials science at Technische Universitat Darmstadt is making multifunctional nanotubes of goldith the help of Vitamin c and other harmless substances.

The doctoral student in the research group of Professor Wolfgang Ensinger in the Department of Material Analysis is working on making nanotubes of gold.

The metal on the walls of the channels adopts the shape of nanotubes; the film is dissolved then.

the result is-depending on the experimental conditions-a collection of individual nanotubes or an array of hundreds of thousands of interconnected tubes.

"With 1 gram of gold, we could make a nanotube for literally every person on earth."

For example, they are thinking about also using the nanotubes to measure blood sugar.""A subcutaneous sensor could save diabetes patients from having to constantly prick their fingers"thinks Ensinger.

#Nanotubes may restore sight to blind retinas The aging process affects everything from cardiovascular function to memory to sexuality.

or older who have damage to a specific part of the retina will stand to benefit from the nanotube device

#Graphene/nanotube hybrid benefits flexible solar cells Rice university scientists have invented a novel cathode that may make cheap, flexible dye-sensitized solar cells practical.

from nanotubes that are bonded seamlessly to graphene and replaces the expensive and brittle platinum-based materials often used in earlier versions.

In his process, the nanotubes remained attached to the surface substrate but pushed the catalyst up as they grew.

The graphene/nanotube hybrid came along two years ago. Dubbed"James'bond"in honor of its inventor, Rice chemist James Tour, the hybrid features a seamless transition from graphene to nanotube.

The graphene base is grown via chemical vapor deposition and a catalyst is arranged in a pattern on top.

which lifts off and allows the new nanotubes to grow. When the nanotubes stop growing,

the remaining catalyst (the"carpet")acts as a cap and keeps the nanotubes from tangling.

The hybrid material solves two issues that have held back commercial application of dye-sensitized solar cells,

First, the graphene and nanotubes are grown directly onto the nickel substrate that serves as an electrode,

With no interruption in the atomic bonds between nanotubes and graphene, the material's entire area, inside and out, becomes one large surface.

Lou's lab built and tested solar cells with nanotube forests of varying lengths The shortest,

Other nanotube samples were grown for an hour and measured about 100-150 microns. When combined with an iodide salt-based electrolyte and an anode of flexible indium tin oxide,

Tests found that solar cells made from the longest nanotubes produced the best results and topped out at nearly 18 milliamps of current per square centimeter

a tiny hole in a ceramic sheet that holds electrolyte to carry the electrical charge between nanotube electrodes at either end.

30 times better than the best quality factors measured in nanotubes to date. Imagine that the host of a dinner party tries to get his guests'attention by giving a single tap of his oyster spoon on his crystal glass.

and because of this trend it was unthinkable that nanotubes could exhibit giant quality factors. The giant quality factors that ICFO researchers have measured have not been observed before in nanotube resonators mainly

because their vibrational states are extremely fragile and easily perturbed when measured. The values detected by the team of scientists was achieved through the use of an ultra-clean nanotube at cryostat temperatures of 30mk(-273.12 Celsius-colder than the temperature of outerspace!

and by employing an ultra-low noise method to detect minuscule vibrations quickly while reducing as much as possible the electrostatic noise.

since"nanotube resonators are enormously sensitive to surrounding electrical charges that fluctuate constantly. This stormy environment strongly affects our ability to capture the intrinsic behavior of nanotube resonators.

For this reason, we had to take a very large number of snapshots of the nanotube's mechanical behavior.

Only a few of these snapshots captured the intrinsic nature of the nanotube's dynamics, when the storm momentarily relented.

During these short quiet moments, the nanotube revealed its ultra-high quality factor to us"."With the discovery of such high quality factors from this study, ICFO scientists have opened a whole new realm of possibilities for sensing applications,

and quantum experiments. For instance, nanotube resonators might be used to detect individual nuclear spins, which would be an important step towards magnetic resonance imaging (MRI) with a spatial resolution at the atomic level.

For the moment, Adrian Bachtold comments that"achieving MRI at the atomic level would be fantastic. But, for this, we would first have to solve various technological problems that are extremely challenging. n

The new kind of nanotubes also could lead to flexible solar panels that can be rolled up and stored or even"painted"on clothing such as a jacket,

they alter the electrical current through the nanotube materials, signaling the presence of any of those substances,

and monitor the current through the nanotube,"says Zang, a professor with USTAR, the Utah Science Technology and Research economic development initiative."

or toxic chemicals caught by the nanotube, you will see an increase or decrease in the current."

"By modifying the surface of the nanotubes with a polymer, the material can be tuned to detect any of more than a dozen explosives,

which drives the nanotubes through the gradient. The nanotubes move through the gradient until their density matches that of the gradient.

The result is that the nanotubes form separated bands in the centrifuge tube by density.

Since the density of the nanotube is a function of its diameter this method allows separation by diameter.

One property that distinguishes these materials from traditional semiconductors like silicon is that they are mechanically flexible.

Under a strong electric field the cathode emits tight high-speed beams of electrons through its sharp nanotube tips a phenomenon called field emission.

and height of the nanotubes the researchers were able to achieve a fluid flow that enabled an operating ion current at very near the theoretical limit.

To control the nanotubes'growth the researchers first cover the emitter array with an ultrathin catalyst film

The nanotubes grow up under the catalyst particles which sit atop them until the catalyst degrades.

Using their nanotube forest they're able to get the devices to operate in pure ion mode

Therefore replacing copper with nanotube wires should significantly reduce the CO2 EMISSIONS related to the manufacturing and operating of electrical machines.

But the researchers warn that based on their previous research the tendency for the nanotubes to accumulate in sediment could indirectly damage the aquatic food chain in the long term

#Nanotube cathode beats large pricey laser Scientists are a step closer to building an intense electron beam source without a laser.

Tests with the nanotube cathode have produced beam currents a thousand to a million times greater than the one generated with a large pricey laser system.

The tested nanotube cathode requires no laser: it only needs the electric field already generated by an accelerator to siphon the electrons off a process dubbed field emission n

and the nanotubes have outstanding electrical conductivity, and they can effectively separate and transport electrical charges generated from solar energy.

and charge transport at very low nanotube loadings, thereby strongly reducing materials costs o

#Scientists improve microscopic batteries with homebuilt imaging analysis (Phys. org) In a rare case of having their cake

#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 nanotubes overcome a limitation of current patches in which pore walls hinder the transfer of electrical signals between cardiomyocytes the heart muscle's beating cells

Nanotubes can fix that and Jacot who has a joint appointment at Rice and Texas Children's took advantage of the surrounding collaborative research environment.

We thought nanotubes could be integrated easily. Nanotubes enhance the electrical coupling between cells that invade the patch helping them keep up with the heart's steady beat.

When cells first populate a patch their connections are compared immature with native tissue Jacot said.

but the nanotubes forge a path around the obstacles. Jacot said the relatively low concentration of nanotubes 67 parts per million in the patches that tested best is key.

Earlier attempts to use nanotubes in heart patches employed much higher quantities and different methods of dispersing them.

Jacot's lab found a component they were already using in their patches#chitosan#keeps the nanotubes spread out.

Chitosan is amphiphilic meaning it has hydrophobic and hydrophilic portions so it can associate with nanotubes (which are hydrophobic)

and keep them from clumping. That's what allows us to use much lower concentrations than others have tried.

and get to it with the fewest nanotubes possible he said. We can do this if we control dispersion well and use high-quality nanotubes.

The patches start as a liquid. When nanotubes are added the mixture is shaken through sonication to disperse the tubes

which would otherwise clump due to Van der waals attraction. Clumping may have been an issue for experiments that used higher nanotube concentrations Pasquali said.

The material is spun in a centrifuge to eliminate stray clumps and formed into thin fingernail-sized discs with a biodegradable polycaprolactone backbone that allows the patch to be sutured into place.

As a side benefit nanotubes also make the patches stronger and lower their tendency to swell

This is a good example of how it's much better for an application person like Dr. Jacot to work with experts who know how to handle nanotubes rather than trying to go solo as many do said he.

The material is made of graphene nanoribbons atom-thick strips of carbon created by splitting nanotubes a process also invented by the Tour lab

and nanotubes using any method they like and use the shrinking action to compact them into a higher density."

Experimental evidence and theoretical simulation reveal that the good structural match between the carbon atom arrangement around the nanotube circumference

#Lab unzips nanotubes into ribbons by shooting them at a target (Phys. org) Carbon nanotubes unzipped into graphene nanoribbons by a chemical process invented at Rice university are finding use in all kinds of projects

The Rice lab of materials scientist Pulickel Ajayan discovered that nanotubes that hit a target end first turn into mostly ragged clumps of atoms.

But nanotubes that happen to broadside the target unzip into handy ribbons that can be used in composite materials for strength

When they inspected the resulting carbon rubble they found nanotubes that smashed into the target end first

or at a sharp angle simply deformed into a crumpled nanotube. But tubes that hit lengthwise actually split into ribbons with ragged edges.

Single-wall nanotubes do just the opposite; when the tube flattens the bottom wall hits the inside of the top wall

Ozden explained that the even distribution of stress along the belly-flopping nanotube which is many times longer than it is wide breaks carbon bonds in a line nearly simultaneously.

The researchers said 70 to 80 percent of the nanotubes in a pellet unzip to one degree or another.

If a nanotube reaches the target at a 90â°angle (head-on) it will break and deform quite drastically.

However if it is parallel to the target upon impact the nanotube will unzip resulting in a 2d graphene nanoribbon.

since previous simulations have shown that nanotubes break into pieces when subjected to large mechanical forces. Researchers Sehmus Ozden et al. at Rice university in Houston Texas US;

and the Indian Institute of Science in Bangalore India have published a paper on the results of their high-impact nanotube collision experiments in a recent issue of Nano Letters.

Because it was not possible to directly observe the impact due to the nanotubes'small size

and high speed the researchers analyzed the differences in the nanotubes using a transmission electron microscope before and after the impact to extract useful information about

Although each bundle of nanotubes (the pellet) was shot perpendicular to the target the individual randomly aligned nanotubes impacted the target at different angles.

At a 90â°impact angle the nanotubes deformed along the radial direction essentially being smashed like the front of a car in a head-on collision.

At a 45â°impact angle the nanotubes became partly deformed and partly unzipped. At a 0â°angle the nanotubes were unzipped completely

when shot at the aluminum target. The researchers explain that the unzipping occurs on the scale of femtoseconds.

In that short time many atoms along the side of the nanotube become stressed due to the impact resulting in the breaking of the carbon bonds in a straight line along the side of the nanotube.

Many of these atoms ended up being ejected from the nanotube rather than having their bonds neatly broken as in the 0â°impact angle scenario.

By demonstrating for the first time that nanotubes can be unzipped quickly through mechanical means the new study offers a clean-cut a clean chemical-free way to produce high-quality graphene nanoribbons.

As the researchers explained graphene nanoribbons have certain advantages over both nanotubes and graphene that make them attractive for applications.

Instead of working so hard to force nanotubes to do something that they are not good for,

The team created silicon dioxide (Sio2) nanotube anodes for lithium-ion batteries and found they had over three times as much energy storage capacity as the carbon-based anodes currently being used.

The paper,"Stable Cycling of Sio2 Nanotubes as High-performance Anodes for Lithium-Ion Batteries,"was published online in the journal Nature Scientific Reports.

There key finding was that the silicon dioxide nanotubes are extremely stable in batteries, which is important

Specifically, Sio2 nanotube anodes were cycled 100 times without any loss in energy storage capability and the authors are highly confident that they could be cycled hundreds more times.

The researchers are focused now on developed methods to scale up production of the Sio2 nanotubes in hopes they could become a commercially viable product t

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