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The researchers created the tiny transistor by simultaneously applying a force and low voltage which heated a carbon nanotube made up of few layers until outer tube shells separate, leaving just a single-layer nanotube. The heat and strain then changed the "chilarity" of the nanotube, meaning the pattern in which the carbon atoms joined together to form the single-atomic layer of the nanotube wall was rearranged. The result of the new structure connecting the carbon atoms was that the nanotube was transformed into a transistor. Professor Golberg's team members from the National University of Science and Technology in Moscow created...

Creating the super-strong material out of something harmful could kill two birds with one stone. _______________________________________________________________________________________________ The concentration of atmospheric carbon dioxide is at its highest levels in hundreds of thousands of years and as matters get worse, it's more crucial than ever to find a way to reverse it. A study released earlier this month presents a novel idea with what to do with the gas humanity can't seem to stop making: Turn it into something useful. Specifically, high-quality carbon nanotubes. The main cause of global warming, carbon dioxide is a heat-trapping gas that is released through using fossil...

Scientists, including those from Northeastern University in the U.S., developed carbon nanotube pores that can exclude salt from seawater. The team found that water permeability in carbon nanotubes (CNTs) with diameters of 0.8 nanometre significantly exceeds that of wider carbon nanotubes. The nanotubes, hollow structures made of carbon atoms in a unique arrangement, are more than 50,000 times thinner than a human hair. The super smooth inner surface of the nanotube is responsible for their remarkably high water permeability, while the tiny pore size blocks larger salt ions. “We found that carbon nanotubes with diameters smaller than a nanometre bear...

Enhanced single-walled carbon nanotubes offer a more effective and sustainable approach to water treatment and remediation than the standard industry materials—silicon gels and activated carbon—according to a paper published in the March issue of Environmental Science Water: Research and Technology. RIT researchers John-David Rocha and Reginald Rogers, authors of the study, demonstrate the potential of this emerging technology to clean polluted water. Their work applies carbon nanotubes to environmental problems in a specific new way that builds on a nearly two decades of nanomaterial research. Nanotubes are more commonly associated with fuel-cell research. “This aspect is new—taking knowledge of carbon...

MIT has found a completely unexpected set of changes: Inside the tiniest of spaces — in carbon nanotubes whose inner dimensions are not much bigger than a few water molecules — water can freeze solid even at high temperatures that would normally set it boiling. ... “If you confine a fluid to a nanocavity, you can actually distort its phase behavior,” Strano says, referring to how and when the substance changes between solid, liquid, and gas phases. Such effects were expected, but the enormous magnitude of the change, and its direction (raising rather than lowering the freezing point), were a...

Process node scaling is becoming very expensive Carbon nanotubes have long been proposed as a significant substrate replacement to transform the chip design industry as we know it. They can operate using substantially less electrical charge and are six to ten times faster than silicon, yet due to their incredibly small size they have proven difficult to work with. The search for silicon alternativesOver the past 62 years since the first working silicon transistor was made at Bell Labs, companies have used different doping concentrations to influence electron mobility on circuit designs. But over the past half-decade, the industry...

Nanotube wires self-assemble under the influence of a directed electric field from the Tesla coil. Credit: Jeff Fitlow ======================================================================================================== Scientists at Rice University have discovered that the strong force field emitted by a Tesla coil causes carbon nanotubes to self-assemble into long wires, a phenomenon they call "Teslaphoresis." The team led by Rice chemist Paul Cherukuri reported its results this week in ACS Nano. Cherukuri sees this research as setting a clear path toward scalable assembly of nanotubes from the bottom up. The system works by remotely oscillating positive and negative charges in each nanotube, causing them to chain together...

Above: IBM's carbon nanotubes have tiny circuits that are fractions of a meter apart.Image Credit: IBM Carbon nanotubes are the leading candidate to replace silicon in semiconductor chips after the decades-long run of silicon electronics runs out. And IBM is hoping to usher along that transition with a new breakthrough being announced today.In the October 2 issue of the journal Science, IBM researchers say they have overcome one of the most daunting challenges around carbon nanotube transistors, which are the building blocks of electronic circuits with dimensions that are measured in billionths of a meter. Carbon nanotubes may be...

Spiders sprayed with water containing carbon nanotubes and graphene flakes have produced the toughest fibers ever measured, say materials scientists. Spider silk is one of the more extraordinary materials known to science. The protein fiber, spun by spiders to make webs, is stronger than almost anything that humans can make. The dragline silk spiders use to make a web’s outer rim and spokes is amazing stuff. It matches high-grade alloy steel for tensile strength but is about a sixth as dense. It is also highly ductile, sometimes capable of stretching to five times its length. This combination of strength and...

A team of researchers working in Italy has found that simply spraying a spider with a carbon nanotube solution can cause the spider to spin stronger webs. In their paper they have uploaded to the preprint server arXiv, the team describes their experiments with both graphene and nanotube solutions and what happened when they sprayed it on ordinary spiders. As the researchers note, while silk production using silkworms has been quite successful, doing the same to harvest silk from spiders has not, (because of their territorial traits, the complex nature of the silk they make and their cannibalistic tendencies) which...

IBM's researchers have made another breakthrough in their development of carbon nanotube technology, packing more than 10,000 working transistors made of the substance onto a single chip. It is now a decade since IBM first announced a process for fabricating carbon nanotubes in a way that could make them usable for processors. Although silicon has allowed the industry to keep making transistors smaller and smaller, it does not work properly at the nanoscale. Another substance will have to take over for the really tiny processors of the future. Such processors will be needed to make computing devices and sensors smaller...

Researchers in Korea and the US have shown that modified carbon nanotubes can protect brain tissue from the damage caused by ischaemic stroke, where the blood supply to the brain is interrupted. The work could lead to new treatments to help the brain repair itself after this type of stroke.Sung Su Kim, of Chung Ang University in Seoul, and colleagues treated commercially available carboxylated nanotubes with a nitrogen and hydrogen plasma, resulting in positively-charged amine groups on the surface of the nanotubes. These amine-modified nanotubes were then injected in the brains of rats. A week later ischaemic stroke was artificially induced in the rats by surgery....

A team of scientists at MIT have discovered a previously unknown phenomenon that can cause powerful waves of energy to shoot through minuscule wires known as carbon nanotubes. The discovery could lead to a new way of producing electricity, the researchers say. The phenomenon, described as thermopower waves, “opens up a new area of energy research, which is rare,” says Michael Strano, MIT’s Charles and Hilda Roddey Associate Professor of Chemical Engineering, who was the senior author of a paper describing the new findings that appeared in Nature Materials on March 7. The lead author was Wonjoon Choi, a doctoral...

(PhysOrg.com) -- A team of scientists at MIT have discovered a previously unknown phenomenon that can cause powerful waves of energy to shoot through minuscule wires known as carbon nanotubes. The discovery could lead to a new way of producing electricity, the researchers say.The phenomenon, described as thermopower waves, “opens up a new area of energy research, which is rare,” says Michael Strano, MIT’s Charles and Hilda Roddey Associate Professor of Chemical Engineering, who was the senior author of a paper describing the new findings that appeared in Nature Materials on March 7. The lead author was Wonjoon Choi, a...

Further evidence for the asbestos-like effects of carbon nanotubes has emerged from a new study in mice. The study shows for the first time that the tubes reach the outer lining of the lung when inhaled - as asbestos does. But researchers say the results should be interpreted with caution.Carbon nanotubes, like asbestos, have high aspect ratios; in other words, they are long and thin, meaning they have the potential to get stuck when trying to cross the two layered membrane - the pleura - separating the lung from the chest wall. In the case of asbestos, fibres can dwell...

Japanese researchers have made ultra-thin metal wires by growing them inside carbon nanotubes. It is hoped that the research - which can make wires only a single atom in diameter - could provide interesting clues to the best components for future nanoelectronic devices. Atom-thin metal wires show many novel electronic properties - but the wires are so fragile and prone to oxidation that they have been difficult to study. Ryo Kitaura and colleagues at Nagoya University solved this problem by growing the wires encased within protective nanotubes. This means that their properties can be measured and mapped. 'The process [of growing the...

Sticky nanotubes that trap bacteria like flypaper can be used to identify bacterial infections in seconds rather than days, report Spanish chemists. Although only tested on the typhus-causing Salmonella typhi bacteria so far, if the process can be applied more widely it could revolutionise bacterial testing in the medical and food industries. Detecting bacteria is currently a laborious process, requiring several stages that can take up to two days. Instead, this new method promises to be as easy as testing for pH, say researchers at the Universityof Rovira i Virgili in Catalonia, Spain. The technique uses carbon nanotubes coated with aptamers -...

DNA could be the answer to sorting different kinds of carbon nanotubes, say US researchers. Short strings of synthetic DNA wind onto nanotubes in a very sequence-dependent way, which has allowed researchers to separate 12 of the most common types of tubes from the inevitable mixtures that form when nanotubes are synthesised. Since the physical and electronic properties of nanotubes are heavily dependent on the size and structure of the tube, separating the mixtures could lead to much more effective nanotube-based devices and even ways of making specific types of tubes selectively.Ming Zheng of Dupont Central R&D, Delaware, and Anand Jagota from...

Nanotubes help turn carbon dioxide and water into natural gas. The nanotubes helped to turn water vapour and carbon dioxide inside a chamber into methane.Nano Lett. Researchers have used sunlight to convert carbon dioxide and water vapour into a range of fuels faster than ever before, thanks to a nanotube catalyst.Materials scientist Craig Grimes and his colleagues at Pennsylvania State University in University Park have used hollow titania (titanium dioxide) nanotubes around 135 nanometres wide and a tenth of a millimetre long to catalyse the reaction. Scientists have used titania nanoparticles to speed up this process before, but Grimes and...

We need technologies that will allow our bodies to be repaired as thoroughly as we repair our cars. Some UCSD researchers find that titanium nanotubes can cause stem cells to become osteoblasts that speed bone repair. San Diego, CA, January 29, 2009 --Engineers at the University of California at San Diego have come up with a way to help accelerate bone growth through the use of nanotubes and stem cells. This new finding could lead to quicker and better recovery, for example, for patients who undergo orthopedic surgery.