Conversion efficiencies of the best research solar cells worldwide from 1976 through 2011 for various photovoltaic technologies; efficiencies determined by certified agencies/laboratories. Credit: NREL.

The steady march to grid parity for solar energy devices continues: A Santa Clara, Calif., maker of gallium arsenide photovoltaic panels, Alta Devices, announced Tuesday that the NREL verified that its top-line panels operate at 23.5% efficiency. The ability to deliver an entire high-efficiency panel is a big step forward for the company’s business, which last year achieved verified record-setting efficiencies as high as 28.2% with a single, single-junction PV cell.

This looks to be a record efficiency-level for PV panels. Although, as the chart above indicates, NREL has verified higher efficiencies in other PV arrangements, these have been for a single or small sets of PV cells, not full panels. (It should probably be noted that Sanyo asserts that its in-production silicon heterostructure (HIT) panels come near to the numbers achieved by Alta, but this has not been verified by NREL.)

In a news release, Alta Devices explains a little bit about its interest in GaAs-based devices. The company says, “Alta chose to focus on GaAs because of its intrinsic efficiency advantages as well as its ability to generate electricity at high temperatures and in low light. This means that Alta’s panels have substantially higher energy density than other technologies, generating more kilowatt–hours of energy over the course of a year in real life conditions.”

Some investors have been cautious about GaAs-based solar technologies because they generally have appeared to require higher-priced materials than, for example, silicon. But the company says, “though GaAs is known for being expensive to produce, Alta has invented a manufacturing technique that enables extremely thin layers of GaAs that are a fraction of the thickness of earlier GaAs solar cells. Alta’s cells are about one micron thick… In utilizing very thin devices that have the highest energy density possible, the cost of the material needed in Alta panels remains low and the potential costs of an entire solar energy system based on Alta’s technology could be dramatically reduced.”

Alta deposits the GaAs on a thin, flexible film substrate. By focusing on this form factor, Alta says its film “has the potential to be integrated in wholly unique ways and into a variety of applications, including roof and building materials, and numerous military, consumer and transportation products.”

The company was cofounded by two well known California scientists engaged in academic-based energy research, CalTech’s Harry Atwater and University of California at Berkeley’s Eli Yablonovitch. Atwater is director of the Energy Frontier Research Center on Light-Matter Interactions and director of the Resnick Institute for Science, Energy and Sustainability, and Yablonovitch is director of the NSF Center for Energy Efficient Electronics Science, at their respective schools. Alta has received venture capital funding from high profile groups, such as August Capital and Kleiner Perkins Caufield & Byers.

In a recent story on the Lawrence Berkeley National Lab website, Yablonovitch offered a fundamental defense of GaAs. He said, “Gallium arsenide absorbs photons 10,000 times more strongly than silicon for a given thickness but is not 10,000 times more expensive,” says Yablonovitch. “Based on performance, it is the ideal material for making solar cells.”

But the trick is to extract the high efficiency from GaAs. In a June 2011 release, Yablonovitch explained, “Up until now it was understood that to increase the current from our best solar materials, we had to find ways to get the material to absorb more light. But, the voltage is a different story. It was not recognized that to maximize the voltage, we needed the material to generate more photons inside the solar cell. Counterintuitively, efficient light emission is the key for these high efficiencies.”

How are these efficiencies and energy density being achieved? For one thing, it required some open-mindedness. The LBL story describes that a leap in logic had to occur: “Past efforts to boost the conversion efficiency of solar cells focused on increasing the number of photons that a cell absorbs. Absorbed sunlight in a solar cell produces electrons that must be extracted from the cell as electricity. Those electrons that are not extracted fast enough, decay and release their energy. If that energy is released as heat, it reduces the solar cell’s power output. [LBL's Owen Miller] calculated that if this released energy exits the cell as external fluorescence, it would boost the cell’s output voltage. ‘This is the central counter-intuitive result that permitted efficiency records to be broken,’ Yablonovitch says.”

“In the open-circuit condition of a solar cell, electrons have no place to go so they build up in density and, ideally, emit external fluorescence that exactly balances the incoming sunlight. As an indicator of low internal optical losses, efficient external fluorescence is a necessity for approaching the [theoretical efficiency] limit,” Miller said.

In other words, the Alta Devices PV panels achieve high efficiency by emitting certain light while converting solar energy, instead of allowing excess electron energy to build up internal heat.

On the processing side of things, the company says it “is making substantial progress on the build-out of its pilot manufacturing line, which uses mostly off–the–shelf equipment with some proprietary optimizations unique to Alta’s process. Moreover, Alta is starting to plan for full–scale production, with activities such as building strategic manufacturing partnerships and selecting its first large, commercial manufacturing site.”

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Graphene nanoribbon band structures for arm-chair type. Tightbinding calculations show that armchair type can be semiconducting or metallic depending on width (chirality). Credit: SR Mehrotra and G Klimeck; Wikipedia.

The Office of Naval Research has announced that it is interested in encouraging “research and innovation in bottom-up chemical synthesis and assembly of carbon, particularly graphene, based electronic devices and circuits with atomic precision and Angstrom resolution,” and has just issued a Basic Research Challenge to stir up interest and submission of ideas.

The program, says ONR in the announcement, will support basic research on building new electronic devices and circuits “from the molecular level up, using molecular synthesis, surface catalytic chemistry and other novel techniques.”

ONR says it envisions several stages to the projects it hopes to fund. The beginning emphasis will be on “synthesis of graphene nanostructures with controllable predetermined shape and atomically sharp edges, e.g., graphene nanoribbons.” Dimensionally, it says it is interested in nanoribbons a few nanometers wide and longer than 100 nanometers. During this initial phase, ONR also wants to have methods developed to transfer the nanoribbon to non-metallic substrates.

The middle phase of the projects would focus on “synthesis of molecules that perform as graphene based circuit elements, and eventually, to rationally design and assemble them into ‘circuit molecules’.”

Eventually, ONR wants the projects’ emphasis to evolve into creating “ways to interface the molecularly derived graphene circuit elements and circuits, and impedance match them, with top-down manufactured systems at micrometer scale” and also “interface with other molecules, such as other carbon allotropes (CNT, C60 etc.), graphene derivatives (hydrogenated and/or fluorinated graphene) and other closely related noncarbon materials (hexagonal boron nitride, silicene, MoS₂, etc.).”

The Navy imagines funding somewhere between two and six different projects using a fund of $6 million spread out over five years.

Have some ideas for ONR? Although not required, interested individuals are encouraged to first submit short white papers, which will be evaluated to determine whether the technology advancement proposed appears to be of particular value. White papers should be submitted by March 31, 2012, to Chagaan Baatar (chagaan dot baatar at navy dot mil) and Paul Armistead (paul dot armistead at navy dot mil). Baatar and Armistead also serve as technical contacts for the program.

Full proposals submissions should be made through grants.gov by May 1, 2012. The ONR announcement mentions finding the grant opportunity using the funding number ONRBAA-12-001, but I could only find it by searching using the funding number 12-SN-0003. Be sure to check out the submission information detailed in the ONR’s announcement. Things will be happening fast: ONR says final funding decisions will be made by May 15 and grants will be awarded July 1.

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Photographs of sample films at room temperature. Credit, Gao et al.; RSC Energy Environ. Sci.

The notion of making functional and flexible ceramic foils is fascinating, but a little counterintuitive, isn’t it?

Thus, I am always intrigued when new techniques and applications are discovered. A while back I wrote about a group from ETH Zurich that mastered ultrathin, transparent and flexible foils using yttria stabilized polycrystalline tetragonal zirconia.

This weeks brings news of another transparent and flexible film based on vanadium dioxide developed by Chinese researchers at the Shanghai Institute of Ceramics, including ACerS member Yanfeng Gao. The new VO₂ film is being eyed for use in thermochromic windows, which retain transparency in the visible range but dynamically regulate the passage of wavelengths that transfer solar heat and energy in the ultraviolet and infrared ranges.

Smart window researchers have had an interest in VO₂ because they’d like to exploit a particular property: At 68°C (in the case of VO₂ bulk single crystals), the material undergoes a reversible, thermally induced phase transition that shifts the optical properties in the near-infrared region from a low-temperature transparent state to a more reflective state.

In an email, Gao says materials based on VO₂ nanoparticles, particularly VO₂ foils that easily can be used with glass panels, are attractive for applications in construction and automotive industries. Heretofore, making such foils from solutions of nanoparticles has been tricky and unreliable because of the instability of the nanoparticles. But, Gao and his colleagues report in a paper in the Royal Society of Chemistry’s journal, Energy and Environmental Science, that they have figured out a new process that solves previous shortcomings and may be scalable to large-area mass production.

Gao, who works in SIC’s State Key Laboratory of High Performance Ceramics and Superfine Microstructure, says, “In this paper, we report a novel all-solution process that can be used to prepare transparent, stable and flexible VO₂-based composite films. These films exhibit UV-shielding properties and an excellent temperature-responsive thermochromism in the near infrared region.”

The breakthrough? Gao says the answer came when the group coated the VO₂ nanoparticles with a thin SiO₂ shell. “The shell, Gao says, “significantly improved their anti-oxidation and anti-acid abilities.”

Essentially, the VO₂ nanoparticles are given a SiO₂ shell using tetraethyl orthosilicate (the thickness of the shell can be fine-tuned) and treated with a silane couple to increase dispersion. The last step is to cast the suspension on a PET substrate.

At 13.6% solar modulation efficiency, the researchers report in the paper that their VO₂-based film is able to match the efficiency levels of other thermochromic films. This is also considerably higher than VO₂ films produced by sputtering and other methods.

Gao says, “Traditional glass foils are usually based on thin notable metal layers for reflection of solar irradiation or organic dyes that can absorption solar heat. … The stability of these kinds of foils is still questionable. To our knowledge the current research reports on the first VO₂ ceramic foils, and more importantly, the foils show excellent optical properties (visible transmittance and solar modulation ability, maybe the best in the world.).

As far as “smart” performance goes, Gao et al. report in the paper that they observed while testing a typical sample of the VO₂ film, “… in a heating cycle from 35°C to 85°C, the transmittance at 1500 nm decreased from 57.7% (at 35°C) to 14.9% (at 81°C) gradually…  In a cooling cycle, the transmittance of film increased from 14.9% (at 75°C) to 57.7% (at 35°C).”

The promise of increased energy efficiency via thermochromic windows has drawn worldwide attention. Gao says it is a big concern for developing countries, such as China, which already has buildings occupying 52 billion square meters “waiting new techniques to improve their energy efficiency and to reduce greenhouse gas emissions. We are aiming to develop a new material along with a novel process that can be finally commercialized and used to for building glasses.”

Gao says scaling the group’s technique to large-area production is the next challenge, and says that a collaborative effort is worthwhile. “This method should be considered as a basis for mass production,” he says, “The method should combine with some techniques to efficiently fabricate and to improve performance-cost ratios. … We hope that colleagues working in related fields can join to consider innovations based on the current technology. As an important part of an eco-home, we hope that such kind of smart windows can be applied practically in the near future.”

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On relaxations and aging of various glasses

Slow relaxation occurs in many physical and biological systems. “Creep” is an example from everyday life. When stretching a rubber band, for example, the recovery to its equilibrium length is not, as one might think, exponential: The relaxation is slow, in many cases logarithmic, and can still be observed after many hours. The form of the relaxation also depends on the duration of the stretching, the “waiting time.” This ubiquitous phenomenon is called aging, and is abundant both in natural and technological applications. Here, we suggest a general mechanism for slow relaxations and aging, which predicts logarithmic relaxations, and a particular aging dependence on the waiting time. We demonstrate the generality of the approach by comparing our predictions to experimental data on a diverse range of physical phenomena, from conductance in granular metals to disordered insulators and dirty semiconductors, to the low temperature dielectric properties of glasses.

Built to withstand almost anything

Thanks to researchers at Department of Homeland Security S&T, communities can fortify today’s critical structures — and design tomorrow’s — to absorb blows and remain open if assaulted by extreme earth, wind, water, fire, or man. A new publication series, aimed at engineers, architects, building owners, city planners, and emergency managers, makes available years of government, industry, and academic research on designs and materials to make buildings and tunnels terror-resistant and terror-resilient. The Building and Infrastructure Protection Series provides architects and engineers a set of aids for designing critical infrastructure to withstand all kinds of hazards…at a cost that won’t break the budget.

Boise State researchers create new way to study ground fractures

Boise State geophysics researchers have created a new way to study fractures by producing elastic waves, or vibrations, through high-intensity light focused directly on the fracture itself. The new technique developed in the Physical Acoustics Lab may help determine if there is a fluid, such as magma or water, or natural gas inside fractures in the Earth. Typically, scientists create sound waves at the surface to listen for echoes from fractures in the ground, but this new technique could provide more accurate information about the cracks because sound does not have to travel to the fracture and back again. The new technique aims to enhance scientists’ abilities to image faults in the Earth, including those man-made through the process of hydraulic fracturing, or fracking.

Antennaless RFID tags developed at NDSU solve problem of tracking metal and liquids

Tracking and identifying metal objects can prove difficult for some radio frequency identification systems. A patent-pending technology developed by a research team at the Center for Nanoscale Science and Engineering at North Dakota State University, Fargo, could solve these RFID tracking problems. The antennaless RFID tag developed at CNSE could help companies track products as varied as barrels of oil to metal cargo contaRFID tag bottleiners. A typical RFID tag is made up of an integrated circuit and an antenna. While there are different types of tags available, many don’t work well on metal objects or on containers filled with liquid. Previous attempts to solve this problem have resulted in bulky tags that are easily destroyed by routine handling. Researchers at the center have developed a patent-pending novel approach, with an antennaless RFID tag, allowing for an inexpensive and manufacturable product tracking solution that meets EPCglobal Standards.

MIT envisions DIY solar cells made from grass clippings

Research scientist Andreas Mershin has a dream to bring inexpensive solar power to the masses, especially those in developing countries. After years of research, he and his team at MIT’s Center for Bits and Atoms, along with University of Tennessee biochemist Barry Bruce, have worked out a process that extracts functional photosynthetic molecules from common yard and agricultural waste. If all goes well, in a few years it should be possible to gather up a pile of grass clippings, mix it with a blend of cheap chemicals, paint it on your roof and begin producing electricity. Talk about redefining green power plants!

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Jim O’Neil, a fellow graduate student a good while ago, liked to say, “Ceramic engineering is all about making big rocks into little rocks, and then making little rocks into big rocks.”

I’ve lost track of Jim, but a new Rapid Communication in the Feb. 2012 Journal of the American Ceramic Society reminded me of his take on our branch of materials science.

The short paper by a Korean team, Son and Jung, describes a novel method of making discrete ferroelectric particles by a method that amounts to making “little rocks out of big rocks” — but on a nanoscale!

The investigators were interested in fabricating PbTiO₃ nanodots for ferroelectric random access memory, which is a promising material for a nonvolatile memory applications.

Demand for smaller devices is driving the development of high density, high performance memories, and further downsizing is starting to run into physical limitations imposed by materials properties and processing.

For example, some types of RAM materials, are susceptible to a surface effect on the memory switching mechanism as they are scaled down. In ferroelectric RAM materials, there is a critical size that is determined by the maximum size of the nonferroelectric component.

Processing, too, imposes size limitations. Several methods have been used to fabricate ferroelectric nanostructures, such as self-assembly, an anodizing aluminum oxide template process, e-beam lithography and dip-pen lithography. According to the paper, PTO nanodots have been fabricated in the 22 nm to 60 nm range by these methods. The smallest PTO nanodots (22 nm) were made by self-assembly, however, the authors note that “these nanodots did not exhibit a canonical piezoelectric hysteresis loop,” even though the critical size for PTO nanodots to exhibit ferroelectricity is a few nanometers. Dip-pen lithography can make nanodots of about 40 nm with good ferroelectric properties. The anodizing aluminum oxide process is not conducive to making dots less than 60 nm.

Son and Jung’s idea was simple: Make a nanodot, whack it with a hammer, anneal to crystallize the shattered pieces and, finally, test for ferroelectricity. Their goal was to fabricate PTO nanodots less than 10 nm diameter with ferroelectric properties.

So, using dip-pen lithography, they made a PTO nanodot that was 40 nm diameter and 25 nm thick. Using an atomic force microscope tip as a hammer, the dot was shattered after “repeated collisions,” that is, they had to beat on it. The resulting nanoparticles ranged in size from several nanometers to a few tens of nanometers, and were of “diverse sizes in both diameter and thickness.”

After crystallization, tests showed that ferroelectric properties were present in a 25 nm dia. x 11 nm thick nanodot and in one that was 10 nm dia. x 8 nm thick. The 10-nm-diameter nanodot, according to the article, is “closer to the theoretical critical size” than has been achieved in other studies. PTO nanodots that were less than about 3 nm thick proved difficult to test because of high leakage currents.

The paper is “Ferroelectric PbTiO₃ Nanodots Shattered Using Atomic Force Microscopy,” Jong Yeog Son, Inhwa Jung, JACerS, Feb. 2012. DOI: 10.1111/j.1551-2916.2011.05026.x.

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• According to reports, approximately 500 tons of molten glass was spilled in an incident on 30th January 2012 at Guardian Industries’ glass manufacturing plant in De Witt, Iowa, US. The glass leak happened during routine maintenance and six fire departments spent approximately five hours pouring cold water on the spill.

• Zimbabwe’s sole glass manufacturer, Zimglass, is set to resume operations in April 2012 after the company secured funding to refurbish its furnaces.

• AGC Glass Company North America has announced that it plans to restart float G1, an idled production line at its Tennessee plant, USA and re-instate 100 jobs once the line becomes operational. The company shut down the production line in 2008 and laid-off approximately 250 people at the time.

• Seeing the promising prospects for container glass, Taiwan Glass Group, Taiwan’s largest glass maker, plans to expand production capacity at its plant in Hsinchu County, northern Taiwan by integrating two old production lines and adding a new one.

• Magnezit Group has acquired Panteleymonovka Refractory Plant (town Gorlovka), one of the biggest enterprises in Ukraine for production of magnesia refractories.

Editor’s note: We welcome Italy-based P. Carlo Ratto to our team of bloggers. Ratto is a former council member at GLG and consultant at RHI AG Glass Division - Monofrax & Refel plants and is business development manager, Fused Cast at Vesuvius Group (Monofrax). For more information, readers are urged to consider joining some of the ceramic-related Linked In groups, such as the Ceramic Engineers’ Group and the Friends of Refractories Group.

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GE’s Super Bowl commercial features engineers making power plant turbines that “make the power that makes the beer.” Credit: GE; NFL.

So, the Super Bowl is all about three things: football, the commercials and the half-time show.

Super Bowl XLVI is history now and will be deconstructed for quite some time. As my football ignorance is vast, I have nothing to add, except to note that it was a good game and more fun to watch than many have been. The only thing I would have changed was the outcome!

But, I’m stoked about the commercials. Did you notice how many materials science commercials there were? I especially like the heroic portrayal of engineers and in the GE commercial, “Power and Beer.”

Here’s what I caught. Did you see any that I missed? Which one did you like best?

1. Bud Light Platinum - Features a stylized beer bottle manufacturing line, which begins with a fantastical blue stream of molten glass. Obviously, it was a CG production, but I would have liked to see a red hot glass flow cool to a blue bottle, and no harm would have come to the beer. The blue molten glass stream felt all wrong. Also, I’m not sure about the marketing thinkology behind naming an amber brew “Platinum,” a metal that definitely is not amber hued, but I will always welcome a materials connection to a consumer product.

2. Bridgestone tires - Bridgestone bought several spots with the theme of “bringing tire technology to the world of sports,” where a team of white-coated engineers used advanced polymer tire technology to engineer footballs, basketballs and hockey pucks with extraordinary properties. The spots struck me as clever, and the depiction of the engineers as friendly caricatures.

3. GE, “Power and Beer” - This was my favorite because it was intelligent, true and relevant. Engineers are shown explaining what turbines are, how they are made and what they do, which is to make power (in this case). The engineers are depicted as genuine and approachable, people we’d like to have a beer with. And, indeed, the commercial shows the GE team stopping at the local pub for a cold one, where the other patrons ask them what they do for a living. Keeping it simple, the answer comes back, “We make the power for making the beer.” We see the “ah-ha” moment dawn, and a cheer erupt for the heroic engineers who make the power for making the beer!

And what about the “Material Girl’s” halftime show? I’m not going to waste any pixels on Ms. M, except to observe that this may have been an historic performance for her—she ended the show wearing more than when the show started. Maturity? Middle age? The former is unlikely; the latter is inevitable.

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A year ago, Corning published a promotional video, “A Day Made of Glass… Made possible by Corning” that provide an intriguing peek into some of the technologies the company is considering—and how it may affect our lifestyles. It proved to be a popular video, racking up well over 17 million views as of today.

As those of us old enough to remember Walt Disney’s movies about the future of communities, transportation and space, these visionary presentations are more informed guesswork than prophecy. Sometimes (most times?) these ideas just don’t work out for a number of reasons, but the exercise of compiling and publishing these visions helps bring excitement and motivation, especially to young people contemplating careers in science and engineering.

However, smart tech-oriented companies tend to be cautious about sharing their “visions” with the public (Steve Jobs was and Apple still is among those at the most secretive end of the spectrum) because they are both concerned about tipping their hand to competitors and, well, being embarrassed by being wrong about the future.

Corning, however, seems to be closer to the other end of the spectrum and has clearly decided that there is value in teasing the public with how high-tech glass products may disrupt a lot of technologies in our future. Now today, nearly on the anniversary of its first “A Day Made of Glass” video, the company has published an update,  ”A Day Made of Glass, Part 2″ that fleshes out more of Corning’s vision and also incorporates some of the market trends over the last year, such as the huge success of the iPad.

Some of the concepts illustrated in the new video include durable, multitouch screens; colossal- and large-scale edge-to-edge displays; ubiquitous electrochromic windows; entire dashboard surfaces made of soft, flexible glass displays; lightweight auto and sunroof glass; designer-friendly photovoltaic units; antimicrobial glass services for medical applications; and even advances in glass fiber optics.

Corning admits that a lot of these products aren’t right around the corner and acknowledges that there is still a lot of RD&D work that is needed to address existing problems with scalability and price.

To be clear, Corning is smart enough not to reveal all of its product and technology bets in this video. Furthermore, the Apple/Gorilla Glass story underlines how even Corning and other top-tier companies cannot always anticipate what external disruptions of the marketplace will rock their corporate world. Nevertheless, ADMOG Part 2 is an fascinating vision and I predict the number of views in the next year will easily exceed the 17 million of Part 1.

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Integration of Hanse Chemie Inc. USA, into Evonik Goldschmidt Corp.

As of Jan. 1, 2012, the US Hanse Chemie business of Hanse Chemie AG and Nanoresins AG, has been merged into Evonik Goldschmidt Corp. At the same time, Hanse Chemie Inc. USA has been dissolved as a legal entity. The acquisition of the two firms by Evonik was finalized on May 12, 2011. Both companies are headquartered in Germany and produce raw materials and components for the manufacture of sealants, adhesives, molding and casting compounds, and other products. Most of the Hanse Chemie Inc. business is incorporated into the Interface & Performance business line whose activities surrounding the silicone specialties are directed at a variety of industrial markets. Activities in the paint and coatings industry, especially those concerning nanocomposites, extremely fine-particle silicas, are now part of the Coatings & Additives Business Unit of Evonik.

3M launches high density versions of its embedded capacitance material at DesignCon 2012

3M announced the initial availability of its high-capacitance Embedded Capacitance Material at DesignCon 2012, providing design engineers a new way to improve power integrity and reduce electromagnetic interference. Unlike previous 3M ECM versions, which have a maximum capacitance density of approximately 10 nF per square inch, and some existing commercial competitor offerings, which have a maximum capacitance density of approximately 6 nF per square inch, the 3M ECM high-capacitance density solutions offer a capacitance density range from 20 up to 40 nF per square inch, making it the one of the highest capacitance density, halogen-free ECM solutions on the market. This helps design engineers provide hi-fidelity signals, high-signal-to-noise ratio in radio frequencies and higher speed digital signals in a variety of high-performance applications such as small form factor computer hardware, high-performance RF boards, microphones, integrated circuit packaging and consumer electronics.

Mantec consolidates ceramic activities

Mantec, the British technology group with a portfolio of manufacturing businesses based in Stoke-on-Trent, has announced that with immediate effect the three companies previously operated as subsidiaries of the technical ceramic division have now merged into a single, business - Mantec Technical Ceramics Ltd (www.mantectechnicalceramics.com). The three companies involved are Taylor Tunnicliff, Ceramic Gas Products and Fairey Filtration Systems. They have in any case been operating under common management, from the same premises, for the past four years and so this a logical step to take. While the name of Mantec Technical Ceramics will now be the one associated with all administrative, legal, accounting and sales channels, leading brand names owned and manufactured by the group will naturally be retained.

Surmet: SEM of fracture reveals significant grain boundary weakness in lithium fluoride-doped, vacuum hot-pressed and HIPped transparent magnesia spinel

Polycrystalline ceramics with cubic spinel structure transmit well in the visible and mid IR wavelengths of the electromagnetic spectrum. ALON and magnesia spinel are especially attractive, and are leading lightweight transparent armor candidates for future combat systems. These have enormous performance advantage over glass and justify their rapid development. Surmet achieves full density and transparency using the conventional sinter/hot isostatic Ppress process that includes green body formation and high-temperature sintering, followed by HIPping.

Molycorp to receive $390M strategic investment from Molymet; Investment slated to fuel growth and pursuit of vertical integration plans

Molycorp Inc. announced that Molibdenos y Metales S.A. (Molymet), the world’s largest processor of the strategic metals molybdenum and rhenium, has agreed to invest approximately $390 million in the company in exchange for 12.5 million shares of Molycorp common stock. The price of the Molycorp shares to be purchased were valued based on the 20-day volume weighted average share price as of the close of trading on Jan. 30, 2012 plus a 10% premium. Molycorp has agreed to appoint to its board of directors upon the closing of the proposed investment a nominee to be designated by Molymet.

Thermablok aerogel insulation strips installed in new ‘green’ US Border Patrol station in Texas

Crews working construction on the environmentally sustainable Fabens US Border Patrol Station in Clint, Texas have just completed installing 21,000 linear feet of Thermablok aerogel insulating strips on studs throughout the 51,000 square foot facility. The strips reduce thermal bridging, the prime cause of energy loss in buildings. When RVK Architects of San Antonio collaborated with Jacobs Engineering Group of Houston to design the eco-friendly structure already years in the planning, they included Thermablok in the original design. The strips went up easily since they have peel and stick adhesive already attached to the back of the product. The facility also is fitted with solar heaters, sky lights, glazed windows and energy efficient equipment for a low-carbon footprint.

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Screenshot from live webcam of the “Pitch Drop Experiment” at the University of Queensland in Australia. The experiment, begun in 1927, demonstrates the fluid nature of tar pitch at room temperature. Credit: U. Queensland, Australia.

Would you start an experiment that took three years to set up, yielded it’s first result eight years later and generated an average of one data point per decade? Botanists make the news now and then when something like the stinky “corpse flower” blooms once every ten years, but in the physical world, things tend to happen faster.

In 1927, University of Queensland’s first physics professor, Thomas Parnell, want to demonstrate that materials are not always what they seem. Tar pitch, for example, appears to be a brittle solid at room temperature and will shatter if struck with a hammer.

To demonstrate that tar pitch is actually a fluid, Parnell heated a sample of pitch and poured it into a glass funnel with a sealed stem. He allowed three years for the pitch to settle into the funnel, cut the seal in 1930 and waited.

Parnell was a patient man.

The first drop of pitch fell from the funnel in 1938, and a drop has fallen about once per decade since then. The ninth drop fell in November 2000.

Nobody has ever seen any of the drops fall. According to a story in the Brisbane Times, efforts to record the 2000 drip were foiled when the webcam equipment failed. The current curator of the experiment, UQ physics professor John Mainstone, estimates that the next drop will fall sometime around 2013.

The Brisbane Times story reports that the Guinness Book of World Records has recognized it as the longest running experiment in the world. The record is unlikely to be broken. Mainstone estimates that there is enough pitch in the funnel for the experiment to last another century or so. That means a yet-to-be-born Parnell will have to finish the experiment that his great-great-great grandfather started.

And, for those who have lots of time on their hands, the experiment can be watched via live webcam at the university’s webpage about the experiment.

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