— Biocompatible graphene transistor array reads cellular signals — Researchers have demonstrated, for the first time, a graphene-based transistor array that is compatible with living biological cells and capable of recording the electrical signals…
— Researchers find some smartphone models more vulnerable to attack — New research from North Carolina State University shows that some smartphones specifically designed to support the Android mobile platform have incorporated additional features that…
— MIT: New algorithm may improve defensive driving — In 2008, according to the National Highway Traffic Safety Administration, 2.3 million automobile crashes occurred at intersections across the United States, resulting in some 7,000…
— Researchers use CT to recreate Stradivarius violin — Using computed tomography (CT) imaging and advanced manufacturing techniques, a team of experts has created a reproduction of a 1704 Stradivarius violin. Three-dimensional images of…
— Terminator-style info-vision takes step towards reality — The streaming of real-time information across your field of vision is a step closer to reality with the development of a prototype contact lens that could potentially provide the wearer…
— Scientists invent long-lasting, near infrared-emitting material — Materials that emit visible light after being exposed to sunlight are commonplace and can be found in everything from emergency signage to glow-in-the-dark stickers. But until now,…
— Team of researchers develop world's lightest material — A team of researchers from UC Irvine, HRL Laboratories and the California Institute of Technology have developed the world's lightest material - with a density of 0.9 mg/cc - about…
— Humans can control a cursor with power of thought — The act of mind reading is something usually reserved for science-fiction movies but researchers in America have used a technique, usually associated with identifying epilepsy, for…
— Nanoparticles improve solar collection efficiency — Using minute graphite particles 1000 times smaller than the width of a human hair, mechanical engineers at Arizona State University hope to boost the efficiency - and profitability…
Compact high-temperature superconducting cables demonstrated at NIST
A researcher at the National Institute of Standards and Technology (NIST) has invented a method of making high-temperature superconducting (HTS) cables that are thinner and more flexible than demonstration HTS cables now installed in the electric power grid while carrying the same or more current. The compact cables could be used in the electric grid as well as scientific and medical equipment and may enable HTS power transmission for military applications.
Described in a paper just published online, the new method involves winding multiple HTS-coated conductors around a multi-strand copper 'former' or core. The superconducting layers are wound in spirals in alternating directions. One prototype cable is 6.5 millimetres (mm) in outer diameter and carries a current of 1,200 amperes; a second cable is 7.5 mm in diameter and carries a current as high as 2,800 amperes. They are roughly one-tenth the diameter of typical HTS cables used in the power grid. (Standard electrical transmission lines normally operate at currents below 1,000 amperes.)
HTS materials, which conduct electricity without resistance when cooled sufficiently (below 77 K, or minus 196 C/minus 321 F, for the new cables) with liquid nitrogen or helium gas, are used to boost efficiency in some power grids. The main innovation in the compact cables is the tolerance of newer HTS conductors to compressive strain that allows use of the unusually slender copper former, says developer Danko van der Laan, a University of Colorado scientist working at NIST.
'The knowledge I gained while working at NIST on electromechanical properties of high-temperature superconductors was very important for inventing the initial cable concept,' van der Laan says. 'For instance, my discovery that the conductor survives large compressive strains made me realise that wrapping the conductor around a small diameter former would most likely work.'
Van der Laan and NIST colleagues demonstrated the feasibility of the new concept by making several cables and testing their performance. They used an HTS material with a critical current that is less sensitive to strain than some other materials. Although the prototype cables are wound by hand, several manufacturers say mass production is feasible.
NIST researchers are now developing prototype compact HTS cables for the military, which requires small size and light weight as well as flexibility to pull transmission lines through conduits with tight bends. Beside power transmission, the flexible cabling concept could be used for superconducting transformers, generators, and magnetic energy storage devices that require high-current windings. The compact cables also could be used in high-field magnets for fusion and for medical applications such as next-generation magnetic resonance imaging and proton cancer treatment systems.
Or subscribe for our Newsletter, a free e-mail publication. It is published practically every day.
Findings suggest nanowires ideal for electronics manufacturing
New generator produces AC current by stretching wires
Solar power game-changer: 'Near perfect' absorption of sunlight, from all angles
Novel nanocluster to boost thin films for semiconductors