Sentences with phrase «nanotubes by»

He has pioneered the use of density gradient ultracentrifugation (DGU) to purify carbon nanotubes by diameter, electronic type and chirality (degree of twist).

A process revealed last year by Martí and lead authors Chengmin Jiang, a graduate student, and Avishek Saha, a Rice alumnus, starts with negatively charging carbon nanotubes by infusing them with potassium, a metal, and turning them into a kind of salt known as a polyelectrolyte.

Not exact matches

Ultracapacitors using nanotubes have gone on to be a success, notably through FastCap Systems, a firm founded by John Cooley, also from MIT.

SQZ was solving the problem by using its chip - based, gas - pressure system to push in the nanotubes.

Based on computational studies, compared to conventional carbon nanotubes, the nanothreads produced by this method may have outstanding mechanical and electronic properties.

The positively charged rubidium ion that it leaves behind is repelled by the positively charged nanotube and slingshots away (Physical Review Letters, DOI: 10.1103 / PhysRevLett.104.133002).

«The yoctogram mass sensitivity achieved by the Catalan team is certainly spectacular the challenge ahead will be to routinely manufacture nanotube sensors at low cost,» says Rachel McKendry, a nanoscientist at University College London.

* Top Image: Adapted with permission from Elaboration of Nanostructured Biointerfaces with Tunable Degree of Coverage by Protein Nanotubes Using Electrophoretic Deposition

By applying a voltage across a carbon nanotube — a rolled - up sheet of carbon atoms — the team can generate a powerful electric field.

A thin vest of tiny carbon nanotubes may have the potential to stop bullets without even the bruising left by today's vest technology.

These results are consistent with the idea that semiconducting carbon nanotubes are able to expand the light capture by plant materials to other parts of the solar spectrum such as the green, near infrared and ultraviolet.

The RPI team made the paper battery by first growing an array of carbon nanotubes on a silicon surface and then covering the array in dissolved cellulose (the main constituent of paper).

Researchers say they hastened new cell production by sending electrical surges through the nanotubes, which are also excellent conductors of electricity.

Their suggestions include using a nanotechnology called «resistive memory» to keep electronics humming and using carbon nanotube shielding — originally made by NASA to shield spacecraft from radiation — for protection.

The computer also represents a victory for much - hyped carbon nanotube transistors, created in 1998 by Cees Dekker and his group at Delft University of Technology in the Netherlands.

In early testing, a three - dimensional (3D) fiber - like supercapacitor made with the uninterrupted fibers of carbon nanotubes and graphene matched or bettered — by a factor of four — the reported record - high capacities for this type of device.

Scientists funded by the NSF are working to synthesize, characterize and functionalize boron nitride nanotubes and boron nitride nanoribbons to create new electronic and optical materials with tunable properties.

Inspired by geckos» sticky feet, scientists are developing adhesive tapes — by rooting columns of nanotubes in flexible polymer pieces — that stick many times better than a gecko's foot.

By coating the wings of a Blue Morpho butterfly with carbon nanotubes that magnify the effect, researchers there made an insect into a sensor that changes color when its temperature changes a mere 1 / 25th of a degree.

The panel, which was commissioned by U.K. science minister David Sainsbury in July 2003, concluded that nanoparticles and nanotubes should be treated as new chemicals and their impacts on health and the environment be tested under existing U.K. and E.U. legislation.

But in a paper posted online today in Nature Nanotechnology, the MIT team, led by materials scientist Yang Shao - Horn, took a very different approach: using carbon nanotubes to replace the oxide - based positive electrode.

Instead, the device developed by physicist Kaili Jiang of Tsinghua University in Beijing is just a thin film of nanotubes.

Optical rectennas operate by coupling the light's electromagnetic field to an antenna, in this case an array of multiwall carbon nanotubes whose ends have been opened.

«To conclude,» Banhart writes, «a connection between carbon nanotubes was achieved by depositing carbon contamination selectively at nanotube junctions with an electron beam.»

The hitch, so far, has been that the most promising tubes — single - walled nanotubes (SWNTs), consisting of one layer of carbon atoms arrayed like rolled - up chicken wire — can be made only by the thimbleful and can cost up to $ 2000 a gram.

Their real breakthrough, however, is discovering the use of an intermediate dielectric coating (hafnium) to block the quenching of the free electrons in the metal by the CNTs, allowing the nanotubes to function uninhibited.

Bond and her collaborators are using metal - coated nanotubes bunched together like a jungle canopy to amplify the signals of both the incident and Raman scattered light by exciting local electron plasmons.

By preserving the electrons and enhancing the light through the use of nanotube jungles, the team is able to significantly increase the SERS» detection sensitivities in CNTs structures.

By the integration of smallest carbon nanotubes into a nanostructured waveguide, they have developed a compact miniaturized switching element that converts electric signals into clearly defined optical signals.

The joint research team, led by LLNL Engineer Tiziana Bond and ETH Scientist Hyung Gyu Park, are using spaghetti - like, gold - hafnium - coated carbon nanotubes (CNT) to amplify the detection capabilities in surface - enhanced Raman spectroscopy (SERS).

However, purified single - walled nanotubes in THF retarded plant development by 45 percent compared to single - walled nanotubes in water, suggesting the nanotubes act as a carrier for the toxic substance.

In 1999, a group led by Mathieu Kociak and Helene Bouchiat at the University of Paris, South, in Orsay, France, reported in Science (28 May 1999, p. 1508) that ropes of 100 or so nanotubes could carry supercurrent between two superconducting electrodes.

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

Researchers have been trying to solve this major problem by creating carbon nanotubes — or CNT — transistors.

The team integrated a three - dimensional array of carbon nanotubes into a microfluidic device by using chemical vapor deposition and photolithography to grow and pattern carbon nanotubes onto silicon wafers.

Carbon nanotubes are tiny hexagonal tubes, made by rolling sheets of graphene, said Rasel Das, first author of the paper.

«Wheat gets boost from purified nanotubes: Toxicity study shows plant growth enhanced by — but only by — purified nanotubes.»

The single - walled carbon nanotubes in new fibers created at Rice line up like a fistful of uncooked spaghetti through a process designed by chemist Angel Martí and his colleagues.

Last year in Science, Ajay K. Sood and Shankar Ghosh of the Indian Institute of Science in Bangalore and colleagues reported inducing an electrical signal by flowing water over single - walled nanotubes (Science, 14 February 2003).

Weisman said it should be possible to noninvasively find small ovarian tumors within rodents used for medical research by linking nanotubes to antibody biomarkers and administering the biomarkers intravenously.

Because different types of tissue absorb emissions from the nanotubes differently, the scanner took readings from many locations to triangulate the tumor's exact location, as confirmed by later MRI scans.

Rice materials scientist Rouzbeh Shahsavari and alumnus Navid Sakhavand first built atom - level computer models of pillared graphene — sheets of graphene connected by covalently bonded carbon nanotubes — to discover their strength and electrical properties as well as their thermal conductivity.

«We wanted to control the nanotubes» lengths and features one - by - one,» said Sleiman, who holds the Canada Research Chair in DNA Nanoscience.

The platform builds the fibrils by combining the properties of the nanotube with a synthetic peptide fragment that is placed inside the cylinder.

Researchers at McGill University have developed a new, low - cost method to build DNA nanotubes block by block — a breakthrough that could help pave the way for scaffolds made from DNA strands to be used in applications such as optical and electronic devices or smart drug - delivery systems.

The study, said George V. Nazin, a professor of physical chemistry, modeled the behavior often observed in carbon nanotube - based electronic devices, where electronic traps are induced by stochastic external charges in the immediate vicinity of the nanotubes.

«Just like a Tetris game, where we manipulate the game pieces with the aim of creating a horizontal line of several blocks, we can now build long nanotubes block by block,» said Amani Hariri, a PhD student in McGill's Department of Chemistry and lead author of the study.

The research was carried out by experts in synthetic and theoretical chemistry, materials and electron microscopy and builds on Professor Khlobystov's concept of carbon nano test tubes (World's tiniest test tubes, Guinness Book of World Records 2005), where the nanotube acts as a container for molecules.

When a commercially produced «forest» of multiwalled carbon nanotubes is cut into with a razor, drawing the blade out slowly pulls out an exquisitely fine web of nanotubes held together by intramolecular van der Waals forces.

About a dozen possible next - generation candidates exist, including tunnel FETs (field effect transistors, in which the output current is controlled by a variable electric field), carbon nanotubes, superconductors and fundamentally new approaches, such as quantum computing and brain - inspired computing.