Archive for March 2009
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You are browsing the archives of 2009 March.
Practicing to use this “mitt” might be a little dicey, but apparently this is a serious proposal. Note, the conference referenced below is the Fifth European Conference on Space Debris hosted by the European Space Agency.
From the transcript of a broadcast by the Australia/ABC-produced World Today:
ELEANOR HALL: Scientists are warning that there’s now so much junk in space that it’s posing a risk to astronauts.
Space scientists are meeting this week in Germany to discuss ways of dealing with the debris problem that they say is so severe that near-Earth flights could soon become too dangerous.
As Barbara Miller reports, the meeting comes just weeks after two satellites crashed into one another over Siberia.
BARBARA MILLER: There are thousands of bits of debris in space and even the smallest can cause significant damage.
[ . . . ]
Kerry Doherty is the Curator of Space Technology at the Powerhouse Museum in Sydney.
BARBARA MILLER: Other possible solutions still sound a little like science fiction.
KERRY DOHERTY: There’ve been various proposals, including actually putting up into orbit large blocks of aerogel, which is an amazingly light substance - it’s actually the lightest solid, the least dense solid known.
And this, supposedly you place it in an orbital location where it can actually attach pieces of space debris in its structure, and then be itself de-orbited.
BARBARA MILLER: So it would almost be like a huge blob of jelly which would go around collecting bits of debris?
KERRY DOHERTY: More like… putting a pad of something directly in the path of the space debris, so in the orbital path, and these things will just block into it, and be captured by the material.
Kind of like a giant catcher’s mitt.
Audio of full segment is here.
Adding that, yes, aerogel has already been used with satellites to catch the dust and other materials around comets, but the aerogel in this context would have to be more backstop than filter.
Los Angeles-based AECOM has announced that one of its divisions, AECOM Environment, and the University of California at Santa Barbara are collaborating on a new Sustainable Nanotechnology Initiative that will be located at UCSB’s Bren School of Environmental Science and Management. AECOM is a worldwide enterprise that describes itself as a provider of “a blend of global reach, local knowledge, innovation, and technical excellence in delivering solutions that enhance and sustain the world’s built, natural, and social environments.”
According to an AECOM release, the goal of the SNI is to begin to understand the environmental risks associated with engineered nanomaterials, according to a company news release.
AECOM says it will collaborate with UCSB to:
“[S]tudy nanomaterial fate and transport, assist in exposure assessment and risk quantification and modeling, develop outreach programs and related training materials for use by industry involved in handling nanomaterials, and conduct ‘real world’ testing of methods and instrumentation for the detection and characterization of nanomaterials.
“New nanotechnology-related products are already impacting global industry and society, and the Bren School’s SNI is critical to helping industry and the public understand the health and environmental implications of nanomaterials,” said Robert Weber, AECOM Environment Group chief executive and a member of Bren’s advisory board. “Our collaboration provides another platform to share expertise, and positions us to better assist our clients in addressing issues associated with some nanomaterials.”
AECOM Environment says it is also working on aquatic toxicity studies for a major commercial producer of carbon nanotubes.
NASA’s Aeronautics Research Mission Directorate and the Air Force Research Laboratory’s Office of Scientific Research have tapped the University of Virginia in Charlottesville, Texas A&M University in College Station and Teledyne Scientific & Imaging LLC of Thousand Oaks, Calif. to be the nation’s hypersonic science centers.
The new centers will focus on Mach 5 aircraft using “air-breathing” propulsion. Of special interest to people in the ceramics field is that these centers will be spending a lot of time working on the materials and structures of such aircraft.
“NASA and the Air Force Research Laboratory have made a major commitment to advancing foundational hypersonic research and training the next generation of hypersonic researchers,” said James Pittman, principal investigator for the Hypersonics Project of NASA’s Fundamental Aeronautics Program at NASA’s Langley Research Center in Hampton, Va. “Our joint investment of $30 million over five years will support basic science and applied research that improves our understanding of hypersonic flight.”
Researchers hope to eventually create an engine that could propel aircraft to speeds exceeding 12 times the speed of sound.
Each center will have a different specialty. The UVA center will be the National Center for Hypersonic Combined Cycle Propulsion. Researchers from the University of Pittsburgh, George Washington University, Cornell University, Stanford University, Michigan State University, SUNY Buffalo, North Carolina State University, ATK GASL Inc. (Ronkonkoma, N.Y.), NIST and Boeing will join the UVA effort.
Teledyne Scientific & Imaging will be the National Hypersonic Science Center for Hypersonic Materials and Structures. Team members include researchers from the University of California, University of Colorado in Boulder, the University of Miami, Princeton University, Missouri University of Science and Technology, the University of California, Berkeley and the University of Texas.
Texas A&M’s project, the soon-to-be National Center for Hypersonic Laminar-Turbulent Transition will concentrate in boundary layer control research. It’s partners include researchers from the California Institute of Technology, the University of Arizona, the UCLA and Case Western Reserve University.
In the past, the work by NASA and the AFOSR sometimes overlapped. The announcement about establishing the three centers follows a review of each other’s technology portfolios.
“The Air Force Office of Scientific Research is very excited to continue our partnership with NASA,” said John Schmisseur, manager for the Air Force Office of Scientific Research’s Hypersonics and Turbulence Program. “The centers represent our first effort to sponsor research jointly.”
NASA and the AFOSR will each kick in approximately $15 million to fund the centers at the rate of about $2 million per year per center. The funding can be renewed for up to five years. NASA and AFOSR received more than 60 proposal before selecting UVA, Texas A&M and Teledyne.
Teledyne is clearly pleased with making the cut.
“For over three decades, Teledyne Scientific & Imaging has been a leader in the development of novel materials such as ultra-high performance ceramic composites, polymer composites, and multi-functional materials,” said Robert Mehrabian, chairman, president, and chief executive officer of Teledyne Technologies. “Teledyne is honored by our selection as a National Hypersonic Science Center from an extremely competitive group of respondents. This effort supports Teledyne’s strategy of leadership in areas of fundamental science and technology critical to the U.S. Government.”
According to its abstract, Teledyne says it will lead an effort to “[R]evolutionize the design of hypersonic vehicles by creating a new class of hybrid, hierarchical materials that achieve substantial breakthroughs in oxidation resistance, maximum useable temperature, and maximum supportable heat flux.”
The company says this will cover:
- Novel routes for combining different materials in tailored morphologies,
- New experimental methods that will enable the direct visualization of the mechanisms that control a material’s performance,
- Multi-scale probabilistic model formulations that can simulate mechanisms at all length scales with high fidelity,
- Novel methods of net-shape processing, and
- The combination of experiments and multi-scale models into a virtual test system that will transform the way in which materials are designed and qualified.
The American Ceramic Society has just published a book on one of the most vibrant areas of energy research and development: Materials Innovations in an Emerging Hydrogen Economy (Ceramic Transactions Volume 202), edited by George Wicks and Jack Simon.
The book is a collection of new papers presented at the 2008 Materials Innovations in an Emerging Hydrogen Economy conference, organized by ACerS and ASM International, and endorsed by The National Hydrogen Association and the Society for Advancement of Material and Process Engineering. It features articles organized into the following five areas:
This volume is an essential resource for those working on hydrogen-related needs and challenges, including those in academia, government, and industry.
NIST and the University of Colorado, operating together as the JILA*, may have just made life a little simpler for those engaged in nano-oriented research by making it easier to use Atomic Force Microscopy.
AFM has become an essential tool in the past two decades because of its ability to build a nanoscale topographic image of a material using a laser and a tiny probe attached to a diving board-like device. Thus far, however, one of the significant downsides to AFM has been its sensitivity to outside “noise” including acoustic noise, vibration and temperature variations. The good news is that the JIAL team believes it has figured out a way to provide “a 100-fold improvement in the stability of the instrument’s measurements under ambient conditions.”
On a practical level, it isn’t surprising that a tool as sensitive as AFM - something that can measure atomic scale physical features and interactions (e.g., bonds) – is also sensitive to the macro conditions within a lab setting. One NIST scientist, Thomas Perkins, put the current situation this way: “At this scale, it’s like trying to hold a pen and draw on a sheet of paper while riding in a jeep.
Until now, this meant that researchers had to invest a lot of time and resources isolating the material and the AFM from outside interference via the use of ultralow temperatures, isolation tables, vacuums, etc. Even these isolation techniques are of no use if the material must be kept in a liquid, as is often the case with biomaterials.
According to a press release, the JILA solution uses a standard AFM probe, but adds two additional laser beams and a precisely marked substrate to sense and respond to the three-dimensional motion of both the test specimen and the probe. The extra beams create a reference system, and any non-material motion of the tip relative to the sample is corrected immediately by compensating for the shift in the substrate.
The method can control the probes position to 40 picometers over 100 seconds, and JILA says it has been able to keep long-term, room temperature drift at 5 picometers per minute, a level they say is a 100-fold improvement over previous ambient-condition AFM measurements.
“This is the same idea as active noise cancellation headphones, but applied to atomic force microscopy,” says Perkins.
An added benefit is that with this reduction in interference, AFM measurements can be performed slower, improving image resolutions by a factor of five.
(* The meaning of “JILA” gets a little confusing and is why I didn’t mention it earlier. It used to stand for Joint Institute for Laboratory Astrophysics, but the joint work between NIST and CU has grown way beyond astrophysics. The term JILA is still used in regard to the joint NIST/CU work, but doesn’t stand for anything anymore.)