I’ve known for some time that glass–ceramic products can be machined, but I actually have never seen it done, so seeing that process and what tools have to be used, what depth of cuts are possible, etc., is what interested me in the above video that Morgan Technical Ceramics recently put online. (Be patient; the juiciest details are in the second half of the under-four-minute video.)
MTC has been promoting its advanced machining capabilities using Corning Macor glass-ceramic, a product the company touts for its mechanical strength as well as its “high dielectric strength, electrical resistivity and ability to withstand high temperature while providing tight tolerance capability.”
Some of the applications mentioned by MTC for machined Macor are ultrahigh or constant vacuum environments, aerospace and nuclear applications, high-heat electrical cutting operations. A number of health equipment-related uses are also mentioned, such as “complex ceramic assemblies for surgical tools, medical instrumentation, and therapeutic and diagnostic equipment.”
Back to the machining of the glass–ceramic, without the use of diamond cutting tools, MTC says it can deliver tolerances +/- 0.0005 inches. The company also says it can machine the Macor to a surface finish of less than 20 micron inches and polished to a smoothness of 0.5 micron inches-roughness average.
Some pretty cool stuff is going on out there…
Bus-sized satellites require massive engines for even the slightest movements, but as far smaller structures become a possibility, a tiny driving mechanism can offer usable thrust. To serve this next-gen tech, MIT saw a need to develop “microthrusters,” which are each the size of a penny and can be mounted to tiny cubed satellites. With thruster components measuring a few microns each, the magnetic levitation system is able to accommodate 500 microscopic tips that emit ion beams in a very small package, serving to push two-pound structures through space. The tiny devices have not made their way into orbit yet, but they have been tested in a vacuum chamber. Because of their size, it’s possible to add several to each satellite, then enabling sophisticated movements for more precise turns.
Samsung will invest between $3-4 billion in an Austin, Texas, plant to renovate a chip-making production line facility in efforts to meet burgeoning demand for its smartphones. It adds to a $1.98 billion investment in South Korea earlier this year to build a new chip-making facility, reports Reuters. The Korea-based smartphone maker will invest the money over the next year in a bid to turn the Austin chip-making plant into a more profitable venture. To put the $3-4 billion investment into sense, Samsung reported a $4.5 billion profit in its Q2 earnings alone.
An unusual type of rock known as a quasicrystal was found deep in the Russian mountains in 2010—the first known naturally occurring quasicrystal. And the most likely origin of that rock was a meteorite from outer space. Now physicist Paul Steinhardt is back with new evidence that his theory about the origin of that Russian quasicrystal is correct, and that meteorite responsible for its transport likely hit Earth around 15,000 years ago, during the last glacial period. Those findings just appeared in the journal Reports on Progress in Physics, published by the Institute of Physics in England.
After more than two weeks of sitting still, NASA’s Mars rover Curiosity is finally set to roll out on the Red Planet with its debut drive on Wednesday. Engineers successfully tested the rover’s steering abilities Monday, Aug. 20, and now they’re ready to turn its six wheels for the first time since Curiosity landed on Mars on Aug. 5, officials announced Tuesday. Curiosity’s first drive on Mars will be a short one. The rover will move about 10 feet (3 meters) forward, turn in place to the right, and then back up a few meters. The whole operation should take the rover about 30 minutes.
Virginia’s “Space Coast” ambitions are getting a big boost as NASA’s Wallops Flight Facility on the Eastern Shore prepares to launch the biggest rocket in its 67-year history. Called the Antares, the rocket is expected to become a workhorse in the commercial space industry over the next several years, ferrying cargo to the International Space Station. The Antares can launch about 13,000 pounds of cargo, or roughly the size of three Volkswagen Beetles, into low-earth orbit. By comparison, last year the biggest private rocket ever to lift off from the West Coast carried 50,000 pounds of cargo. The October launch will be a shakedown cruise not only for the rocket and its spacecraft, but for the new launch pad and its accompanying liquid-fuel complex, which is the first built from scratch in this country in 40 years.
A NASA scientist has just reported that the agency has devised major improvements in aerogel, a development that should speed its use in super-insulated clothing and shoes, higher capacity and efficiency refrigerators, building envelope insulation, heat shields and other products. The report was presented by Mary Ann B. Meador at a meeting of American Chemical Society.
Meador is part of a group working on aerogel at the NASA Glenn Research Center in Cleveland, Ohio.
Although “ordinary” silica aerogel is brittle, is is also very strong, as measured by high compressive strength in comparison to its mass. That is, it resists denting or crushing under load. Thus, it is eyeopening when Meador says, “The new aerogels are up to 500 times stronger than their silica counterparts. A thick piece actually can support the weight of a car.”
According to an ACS news release, the NASA group has devised two new types of aerogel.
One involves making changes in the internal structure of traditional silica aerogels. They used a polymer, to reinforce the networks of silica that extend throughout an aerogel’s structure. Another involved making aerogels from polyimide, an incredibly strong and heat-resistant polymer, or plastic-like material, and then inserting brace-like cross-links to add further strength to the structure.
Heretofore, there have been several practical headaches for aerogel manufacturers, including the above-mentioned brittleness plus difficulties with forming shapes and finding suitable processing and installation methods. The holy grail quest has been to find a low-cost, easy-to-manufacture form of aerogel. Meador makes the remarkable observation that the new aerogels “can be produced in a thin form, a film so flexible that a wide variety of commercial and industrial uses are possible.”
We’ve written in the past how some aerogel has found its way into very limited lines of apparel, such as high-performance (and expensive) jackets atop Mt. Everest. Although I doubt today’s news means that Eddie Bauer or Patagonia will be offering a new aerogel line in time for the holidays, the descriptions of NASA aerogel do make it seem like it should be more conducive to garment assembly lines. Outdoor enthusiasts have other reasons to be happy: Meador also suggests that a new generation of insulated tents and sleeping bags should be attainable.
Building envelope applications are a natural for aerogel, and companies such as Thermoblok, Aspen and Cabot already have been working in these markets. Despite the production, handling and installation problems of silica aerogel, there has been some evidence that just using small strips of the material to prevent thermal bridging at target areas—such as wall studs—can be cost effective. So, cheaper and flexible aerogel strips would go a long way toward making the savings calculation easier. The housing stock in Europe, particularly Northern Europe, is particularly in need of improved insulation (no word yet on the results of the EU’s first Aerocoins aerogel workshop that was to be held this past June). Meador says that the new aerogel is five to 10 times more efficient than existing insulation, with a quarter-inch-thick sheet providing as much insulation as three inches of fiberglass. These insulation values are generally in line with ordinary silica aerogel, so the ease of use is the main thing here.
Meador doesn’t specifically mention it, but the ease of use factor would also be a big plus for the petroleum industry for pipeline insulation. She told me in an telephone interview that NASA has indeed been looking at several private sectors to license the new materials.
But, all of these are spin-off applications. NASA, of course, has a core interest in space, and Meador says the new aerogel may be suitable for improved spacesuit insulation and as a thermal barrier for advanced reentry systems. While the spacesuit application would seem to be relatively straightforward, the thermal barrier use is very novel. When it comes to efforts such as the International Space Station missions and Mars missions, rather than waste space with a thick and fixed heat shield, she says one concept is to store on the reentry vehicle something like a aerogel bag that can be inflated and deployed when needed.
Recently NASA posted a video (below) showing how such an inflated 10-foot-diameter shield could be packed into a 22-inch diameter nose cone, as part of the Inflatable Reentry Vehicle Experiment (IRVE-3) series of tests.
The inflation system was successfully tested July 21, 2012, while being deployed at 7,600 mph, and although the aerogel composition is not specifically mentioned in the news release about the test, Meador tells me that the outer layer of the shield was composed of pyrogel. She says new polyimide aerogel would be a desirable substitute for pyrogel because the latter creates significant dust release problems during the prelaunch handling and folding of the shield.
NASA has provided a brief description in a press release about the success of the test.
An inflation system pumped nitrogen into the IRVE-3 aeroshell until it expanded to a mushroom shape almost 10 feet in diameter. Then the aeroshell plummeted at hypersonic speeds through Earth’s atmosphere. Engineers in the Wallops control room watched as four onboard cameras confirmed the inflatable shield held its shape despite the force and high heat of reentry. Onboard instruments provided temperature and pressure data. Researchers will study that information to help develop future inflatable heat shield designs.
Check out NASA’s video of the launch and deployment here.
Lots of interesting work happening out there:
A team of researchers from Drexel University’s College of Engineering has developed a new method for quickly and efficiently storing large amounts of electrical energy. The researchers are putting forward a plan to integrate into the grid an electrochemical storage system that combines principles behind the flow batteries and supercapacitors. The team’s research yielded a novel solution that combines the strengths of batteries and supercapacitors while also negating the scalability problem. The “electrochemical flow capacitor” consists of an electrochemical cell connected to two external electrolyte reservoirs—a design similar to existing redox flow batteries that are used in electrical vehicles. This technology is unique because it uses small carbon particles suspended in the electrolyte liquid to create a slurry of particles that can carry an electric charge. Uncharged slurry is pumped from its tanks through a flow cell, where energy stored in the cell is then transferred to the carbon particles. The charged slurry can then be stored in reservoirs until the energy is needed, at which time the entire process is reversed in order to discharge the EFC. The main advantage of the EFC is that its design allows it to be constructed on a scale large enough to store large amounts of energy, while also allowing for rapid disbursal of the energy when the demand dictates it. “By using a slurry of carbon particles as the active material of supercapacitors, we are able to adopt the system architecture from redox flow batteries and address issues of cost and scalability,” says Yury Gogotsi, director of the A.J. Drexel Nanotechnology Institute and the lead researcher on the project. “A liquid storage system, the capacity of which is limited only by the tank size, can be cost-effective and scalable. …However, we will need to increase the energy density per unit of slurry volume by an order of magnitude, and achieve it using very inexpensive carbon and salt solutions to make the technology practical.”
(PNAS) Compressed sensing is a method that allows a significant reduction in the number of samples required for accurate measurements in many applications in experimental sciences and engineering. In this work, we show that compressed sensing can also be used to speed up numerical simulations. We apply compressed sensing to extract information from the real-time simulation of atomic and molecular systems, including electronic and nuclear dynamics. We find that, compared to the standard discrete Fourier transform approach, for the calculation of vibrational and optical spectra the total propagation time, and hence the computational cost, can be reduced by approximately a factor of five.
Bioengineered replacements for tendons, ligaments, the meniscus of the knee, and other tissues require re-creation of the exquisite architecture of these tissues in three dimensions. These fibrous, collagen-based tissues located throughout the body have an ordered structure that gives them their robust ability to bear extreme mechanical loading. One popular approach has involved the use of scaffolds made from nano-sized fibers, which can guide tissue to grow in an organized way. Unfortunately, the fibers’ widespread application in orthopaedics has been slowed because cells do not readily colonize the scaffolds if fibers are too tightly packed. Researchers at University of Pennsylvania have developed and validated a new technology in which composite nanofibrous scaffolds provide a loose enough structure for cells to colonize without impediment, but still can instruct cells how to lay down new tissue. Via electrospinning, the team made composites containing two distinct fiber types: a slow-degrading polymer and a water-soluble polymer that can be selectively removed to increase or decrease the spacing between fibers. Increasing the proportion of the dissolving fibers enhanced the ability of host cells to colonize the nanofiber mesh and eventually migrate to achieve a uniform distribution and form a truly three-dimensional tissue. The team is currently testing these novel materials in a large animal model of meniscus repair and for other orthopedic applications.
(Gizmag) A solution containing skin cells and proteins has been shown to speed the healing of venous leg ulcers. While the ulcers can be quite resistant to treatment, a team of scientists is now reporting success in using a sort of “spray-on skin” to heal them. Developed by Texas-based Healthpoint Biotherapeutics, the spray-on solution consists of neonatal keratinocytes and fibroblasts (skin cells), which are suspended in a liquid made up of various proteins associated with blood clotting. It was tested using a group of 228 patients afflicted with the ulcers, all of whom were also treated with compression bandages. It was found that when compared that control group, patients receiving the optimum dosage experienced a 16 percent greater reduction in wound area after seven days. After 12 weeks, they were 52 percent more likely to have achieved wound closure. Not only were the ulcers on patients receiving the optimum dosage more likely to heal, but they also healed quicker - in the control group, ulcers that did heal took an average of 21 days longer to do so. It has been suggested that the spray-on solution may also be useful in treating other types of chronic wounds, such as ischemic and diabetic foot ulcers.
(Tech Beat) A recent paper from the National Institute of Standards and Technology argues that before lab-on-a-chip technology can be fully commercialized, testing standards need to be developed and implemented. Standardized testing and measurement methods, paper author Samuel Stavis writes, will enable MEMS LOC manufacturers at all stages of production-from processing of raw materials to final rollout of products-to accurately determine important physical characteristics of LOC devices such as dimensions, electrical surface properties, and fluid flow rates and temperatures. To make his case for testing standards, Stavis focuses on autofluorescence. Stavis states that multiple factors must be considered in the development of a testing standard for autofluorescence, including: the materials used in the device, the measurement methods used to test the device and how the measurements are interpreted. “All of these factors must be rigorously controlled for, or appropriately excluded from, a meaningful measurement of autofluorescence,” Stavis writes.
NASA’s Space Technology Program has selected Deployable Space Systems of Goleta, Calif. and ATK Space Systems Inc., of Commerce, Calif., for contract negotiation to develop advanced solar array systems. High-power solar electric propulsion, where the power is generated with advanced solar array systems, is a key capability required for extending human presence throughout the solar system. The selected proposals offer innovative approaches to the development of next-generation, large-scale solar arrays and associated deployment mechanisms. These advanced solar arrays will drastically reduce weight and stowed volume when compared to current systems. They also will significantly improve efficiency and functionality of future systems that will produce hundreds of kilowatts of power. These advanced solar arrays could be used in future NASA human exploration and science missions, communications satellites and a majority of other future spacecraft applications.
The Department of Energy’s National Renewable Energy Laboratory recently completed a seven-year project to demonstrate and evaluate hydrogen fuel cell electric vehicles and hydrogen fueling infrastructure in real-world settings. The National Fuel Cell Electric Vehicle Learning Demonstration Final Report shows progress in extending vehicle driving ranges and increasing fuel cell durability and discusses NREL’s key findings from the demonstration project. This effort, funded by DOE’s Office of Energy Efficiency and Renewable Energy, supports the Department’s broader strategy to advance U.S. leadership in hydrogen and fuel cell technological innovation and help the industry bring these technologies into the marketplace at lower cost.
Researchers from the University of Toronto have invented a new device that may allow for the uniform, large-scale engineering of tissue. Scientists manipulate biomaterials into the microdevice through several channels. The biomaterials are then mixed, causing a chemical reaction that forms a “mosaic hydrogel”—a sheet-like substance compatible with the growth of cells into living tissues, into which different types of cells can be seeded in very precise and controlled placements. Unique to this new approach to tissue engineering, however, and unlike more typical methods (for instance, scaffolding), cells planted onto the mosaic hydrogel sheets are precisely incorporated into the mosaic hydrogel sheet just at the time it’s being created, generating the perfect conditions for cells to grow. The placement of the cells is so precise can precisely mimic the natural placement of cells in living tissues. And, by collecting these sheets around a drum, the machine is able to collect layers of cells in thicknesses made to measure: in essence, three dimensional, functional tissues.
Sally Ride changed the world for women in STEM careers forever when she was selected to be the first female space shuttle crew member and made that historic first flight as a mission specialist on Challenger for STS-7 in June 1983. I was in graduate school when her selection to the crew was announced, and my fellow grad students and I realized she had shattered an important “glass ceiling.” As I learned more about her background as a physicist, it seemed that her talents and interests led her almost inevitably to the astronaut corps. The real example she set was to do just that—follow where your interests and talents lead, “barriers’ be damned. Did she even know there was a so-called “glass ceiling?”
Ride was the public face of an important evolution in the astronaut corps at NASA as one of six women selected in 1978 comprising the first class of female astronauts. Without this evolution and Ride’s historic flight, would Christa McCauliffe, for example, have aspired to be the first teacher in space? We will never know for sure, but I suspect not. (Readers will recall that McCauliffe died in the tragic Challenger explosion in 1985.)
After retiring from NASA in 1987, Ride became a science fellow at her alma mater, Stanford University, and joined the faculty of the physics department in 1989. She seemed to understand the import of her career beyond her example to girls thinking of STEM careers, too. In 2001 she founded a company, Sally Ride Science, “to pursue her long-time passion for motivating young girls and boys to stick with their interests in science and to consider pursuing careers in science, technology, engineering, and math.” The company develops classroom materials, festivals, science camps, teacher training and publications to promote Ride’s vision of encouraging children who are interested in STEM careers.
Ride died on July 23 at age 61 of pancreatic cancer. A full biography of her many accomplishments is posted on the Sally Ride Science website.
Sally—thanks for everything.