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Air Force Names Four Candidates to Host New Tanker Reserve Unit

first_imgThe Air Force is considering four locations to host the first Reserve-led KC-46A Pegasus unit — Tinker Air Force Base, Okla.; Seymour-Johnson AFB, N.C.; Westover Air Reserve Base, Mass.; and Grissom ARB, Ind.Officials on Tuesday said the service’s next generation aerial tanker KC-46As will begin arriving at the first Air Force Reserve-led global mobility wing in fiscal 2019.Air Mobility Command and Air Force Reserve Command now will conduct site surveys of each candidate. Officials will grade each location against operational requirements, potential impacts to existing missions, housing, infrastructure and manpower, according to a press release. They also will develop cost estimates to bed down the KC-46A at each candidate base.After briefing the Air Force secretary and chief of staff, the service will select preferred and reasonable alternatives for the operating location. The Air Force plans to announce those alternatives and begin the environmental impact analysis process this summer.“We look forward to the next phase of the process when preferred and reasonable alternatives are announced and our candidate base communities have an opportunity to participate by providing input for the environmental impact analysis,” said Mark Pohlmeier, acting deputy assistant secretary for installations.Tanker units under consideration that are not selected for the KC-46A “will continue to fly their current aircraft for the foreseeable future,” said Chief of Staff Gen. Mark Welsh.  Dan Cohen AUTHORlast_img read more

The Latest on the Space Force

first_imgAir Force photo by Tech. Sgt. Andrew Satran Acting Defense Secretary Patrick Shanahan will nominate leaders to run the proposed Space Force within “weeks, not months,” he said last week, according to Defense News. Shanahan said he has potential nominees in mind.House Armed Services Chairman Adam Smith (D-Wash.) said the administration’s Space Force proposal is “highly problematic” and that his committee will explore “other options,” according to Space News.The Senate Armed Services Committee will hold the first full-scale hearing about the proposal April 11, Sen. Deb Fischer (R-Neb.) announced, according to Space Policy Online. The hearing has not yet been officially announced on the committee’s schedule.Air Force Technology provides an overview of what is known so far about the proposed Space Force. ADC AUTHORlast_img read more

New superconductive properties discovered in old sandwich material

first_img Explore further © 2010 PhysOrg.com This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. (PhysOrg.com) — Japanese researchers, led by Masashi Kawasaki, have discovered that a previously known kind of double layered material created using electrostatic doping can be used as a superconductor. The team, working out of Tohoku University, found that by creating a double layered material using an ionic liquid atop a platform of potassium tantalum oxide (KTaO3) with deposited electrodes, a superconductive state could be made to exist by cooling the result to near absolute zero. They have published their results in Nature Nanotechnology.The authors are quick to point out that they have not created a new superconductive material, but have instead figured out a way to make a known material become superconductive by means of electrostatic doping (using electrostatic properties to control the conductivity of a material). They contrast this with more traditional methods that use chemical doping (adding chemical impurities to a substance to allow for controlling the amount of current that passes through it) which they say means a material might be found that would allow for superconductivity at room temperatures; the holy grail, or course, for many researchers for many years.The first part of the process, which had already been established, works by adding a drop of ionic liquid onto a set of electrodes that have been placed on a base of KTaO3. Doing so causes a double layer to form between the materials with a gap between them of approximately 2nm. When electricity is sent to the electrodes, the charge adheres electrostatically to either side of the gap, creating a sort of capacitor. The next part is new; this is where the team subjected the result to lowered temperatures, measuring the conductivity across the gap as they went. They found that as things got colder the conductivity changed; first, from that of an insulator, then to that of a metal, then to a semiconductor and finally, to that of a superconductor, at around 0.005K, very close to absolute zero.If the research team is successful in a finding another material that would provide the same results at room temperature they would set the stage for a whole new generation of electronic circuits that would be able to operate with very little power and produce little to no heat; options that would likely open the door to new and exciting types of computers and other types of electronic devices. More information: Discovery of superconductivity in KTaO3 by electrostatic carrier doping, Nature Nanotechnology (2011) doi:10.1038/nnano.2011.78Superconductivity at interfaces has been investigated since the first demonstration of electric-field-tunable superconductivity in ultrathin films in 19601. So far, research on interface superconductivity has focused on materials that are known to be superconductors in bulk. Here, we show that electrostatic carrier doping can induce superconductivity in KTaO3, a material in which superconductivity has not been observed before. Taking advantage of the large capacitance of the self-organized electric double layer that forms at the interface between an ionic liquid and KTaO3, we achieve a charge carrier density that is an order of magnitude larger than the density that can be achieved with conventional chemical doping. Superconductivity emerges in KTaO3 at 50 mK for two-dimensional carrier densities in the range 2.3 × 1014 to 3.7 × 1014 cm−2. The present result clearly shows that electrostatic carrier doping can lead to new states of matter at nanoscale interfaces. New property in warm superconductors discovered Image: Nature Nanotechnology (2011) doi:10.1038/nnano.2011.78. For more details, please see the original paper. Citation: New superconductive properties discovered in old sandwich material (2011, May 23) retrieved 18 August 2019 from https://phys.org/news/2011-05-superconductive-properties-sandwich-material.htmllast_img read more