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New 3M micro milling media is alternative to YSZ. Credit: 3M.

Glasstec and Solarpeq return in 2012

Glasstec 2012, the international trade fair for glass production, processing and products and Solarpeq, the international trade fair for solar production equipment, will be held concurrently in Düsseldorf, Germany from Oct. 23 - 26, 2012. Glasstec is the an international trade fair representing the entire value-added process for all facets of the material glass, attracting the mechanical engineering sector, the glass industry and the glazier trade as well as architects, facade planers and civil engineers. Solarpeq, on the other hand, focuses on solar production technology for crystalline and thin-film photovoltaics. This includes manufacturers of machinery, systems and related components as well as materials for the production of solar end products. Exhibit categories at glasstec 2012 will include glass manufacturing/production technology, glass processing and finishing, tools, replacement and spare parts, process control technology for glass and glass-processing machinery as well as glass applications in the construction and façade sector, solar energy and transparent thermal insulation and display glass and laser technologies.

Surmet announces the expansion of its aluminum nitride manufacturing operations

Surmet Corp. of Burlington, Mass., now in its 30th year of successful operations, announces the expansion of its aluminum nitride manufacturing operations in Buffalo, N.Y. This strategic move is in response to the significant growth in global demand for thermal management packaging in the green-tech device industry. Surmet is now one of only a handful of companies worldwide that has the capacity to synthesize high-quality AlN powder in tonnage quantities. Multiple grades including surface modified powders for epoxy filler applications are also available. AlN is eight- to 10-times more thermally conductive than alumina, and its conductivity will not deteriorate with rising temperatures. With a relatively low thermal expansion coefficient, AlN structures meet thermomechanical requirements for many electronic and device components, such as LEDs.

3M announces availability of low-cost micro milling media: new experimental Ppoduct offers performance equivalent to YSZ

3M today announced the availability of an experimental product, Micro Milling Media ZGC, an ultra-low-cost alternative to yttria-stabilized zirconia beads used in high energy mills. The offering can meet the needs for performance-driven, economical nanoparticle dispersions, and help reduce cost and investment in process equipment for those needing to obtain very fine particle sizes. The new high-density (5.8 g/cc) grinding media is as strong and as wear resistant as YSZ beads. Due to its nanocrystalline microstructure (50 - 100 nm) these micro beads feature low friction smooth surfaces and excellent sphericity.

The 150th birthday of Robert Bosch: “I would rather lose money than trust”

Sept. 23, 2011, marks the 150th birthday of Robert Bosch. “I would rather lose money than trust” is one of his best known sayings. Values such as credibility, reliability, and legality formed the basis of his entrepreneurial action - and have lost none of their validity for the company he founded. They are the compass for the Bosch Group’s innovative strength, quality standards, international orientation, and corporate social responsibility. In combination with these, they form the basis for ensuring the company’s lasting business success, as well as its ability to meet the challenges of the future, just as Robert Bosch would have wanted. Apart from the 150th anniversary of the birth of its founder, Robert Bosch GmbH is celebrating its 125th anniversary this year.

Bright “eyes”: Osram’s new prototypes add dynamism to LED lighting for headlights

At ISAL in Darmstadt (Sept. 26-28, 2011) Osram Opto Semiconductors will be showcasing two new LED prototypes for headlights in the shape of the Oslon Black Flat and the Osram Ostar Headlamp Pro. Both combine new chip and package technologies and are equipped with a ceramic converter. Their strengths include high light output even at high currents, a uniform light pattern, thermal stability and a particularly good contrast ratio.

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Credit: DOE

The next few days should be fun for materials scientists and engineers. Tomorrow (May 25) begins the start of a three-day meeting where participants in the DOE’s 46 Energy Frontier Research Centers will begin the initial reporting-out (at least to the public) about what kind progress they have been able to make. There is a PDF brochure about all of the projects here.

These shouldn’t be expected to be anything close to final reports; most of the EFRCs are five-year projects begun in 2009, so they are only about one-third of the way through their work. It’s probably better to think about what will be reported as a combination of status report and dog-and-pony-show. I don’t intend this latter description to be taken as a negative. Political realities being what they are, the DOE and the Obama administration (not to mention the research teams, themselves) need to show how the monies for these projects are being spent, and what some of the eventual payoffs might be.

Unlike ARPA-E, the EFRCs are less applications- and deployment-oriented, and more aimed at basic science and discovery. The idea was to form “dream teams” of researchers who focus on fundamental breakthroughs needed for a new generation of “production, conversion, storage, transmission and waste mitigation.”

Put another way, without advances in basic science, applied technology and engineering would soon be tapped out. At the beginning, five major challenges were described:

• How do we control material processes at the level of electrons?
• How do we design and perfect atom- and energy-efficient synthesis of revolutionary new forms of matter with tailored properties?
• How can we master energy and information on the nanoscale to create new technologies with capabilities rivaling those of living things?
• How do remarkable properties of matter emerge from complex correlations of the atomic or electronic constituents, and how do we control these properties?
• How do we characterize and control matter away – especially very far away – from equilibrium?

One thing EFRCs have in common with ARPA-E projects is that there is considerable risk involved, at least in the sense that not every project is going to hit the jackpot. The EFRCs involve some highly theoretical and esoteric fields of study, so some educated guesswork had to be employed by DOE after it received over $1 billion in proposals (but only had the funding for about one-third). In this case, it’s better to think of the DOE as a venture capitalist who put together a large portfolio of promising investments knowing that there will be an enormous payoff even if only a few elements of the portfolio pan out.

I am sure we will be hearing much more in the next few days, but the DOE is teasing us with developments in four intriguing (and, coincidentally, materials-intensive) areas:

Microscopic Battery Charging — Lead institution: University of Maryland

“This research team has built the world’s smallest lithium battery inside an advanced microscope, and for the first time has been able to watch how its structure changes while it’s being charged. Understanding these changes may enable new design and production of batteries that perform better and last longer.”

Safer Materials for Nuclear Reactors — Lead institution: Los Alamos National Laboratory

“Using a combination of modeling tools, the research team is looking at improving the safety of our nuclear reactors and has discovered possible ’self-healing’ mechanisms for nuclear reactor materials.”

Controlling How Light Interacts with Materials — Lead institution: California Institute of Technology

“Using computer simulation, the research team found that small glass spheres could affect the absorption of sunlight by solar cells by helping to collect and retain light. The small glass spheres could enable efficient coupling of sunlight to ultrathin semiconductor layers, significantly increasing solar cell efficiency and cost-effectiveness.”

Improved LED’s for Homes and Businesses — Lead institution: University of California, Santa Barbara

“A new understanding of the mysterious drop-off in efficiency when LEDs are subjected to strong electric current could eventually help remove barriers to widespread use of low-energy solid-state lighting for homes and industry, greatly reducing power usage.”

In a 2009 interview I did with John Hemminger, who chairs the DOE’s Basic Energy Sciences Advisory Committee, he spoke optimistically about the prospect for EFRC success. ”We’ve developed capabilities to do certain materials engineering at an atomistic, nanometer-scale level combined with revolutionary computational abilities to predict materials properties in advanced of making them. We are at the dawn of a new age called control science, where we can say, ‘these are the properties we need,’ we can predict what the materials need to be like, and we have a way to make them,” he said. “Fundamental understanding of complex materials is essential to crating new energy strategies,” he said.

I also think the EFRCs have a far less discussed benefit: They also represent, to a large extent, investments in promising early-career scientists, and I give credit to DOE Secretary Steven Chu for noting in a news release that, ”In just two years, these research centers have inspired a new generation of talented young Americans to dedicate their careers to meeting our nation’s energy challenges.”

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Schematic showing the architecture of the sensor developed at Princeton. Credit Stephen Y. Chou; Princeton.

Check ‘em out:

Princeton engineers make breakthrough in ultrasensitive Raman-based sensor

Princeton researchers have invented an extremely sensitive sensor that opens up new ways to detect a wide range of substances, from tell-tale signs of cancer to hidden explosives. The sensor, which is the most sensitive of its kind to date, relies on a completely new architecture and fabrication technique developed by the Princeton researchers. It’s operation is based on surface-enhanced Raman scattering.

New tricks from old polymers

Organic solar cells, light-emitting diodes, and thin-film transistors could be enhanced by polymers that mimic the properties of traditional inorganic semiconductors.

DOE and HUD launch energy efficiency loan program

“PowerSaver “loans, backed by the Federal Housing Administration, will be available from 18 lenders in certain regions of the country to provide homeowners up to $25,000 to make energy-efficient improvements, including door and window replacement. The two-year pilot program was just kicked off by the Department of Housing and Urban Development and the Department of Energy.

Chicago’s Willis Tower to become a vertical solar farm

The iconic Willis Tower (formally the Sears Tower) is set to become a massive solar electric plant with the installation of a pilot solar electric glass project. They will replace the windows on the south side of the 56th floor with a new type of photovoltaic glass developed by Pythagoras Solar which preserves daylighting and views while reducing heat gain and producing the same energy as a conventional solar panel. The project could grow to 2 MW in size.

Less is more: Researchers pinpoint graphene’s varying conductivity level

Researchers at North Carolina State University have found one of the first roadblocks to utilizing graphene for fast electronic devices, by showing that its conductivity decreases significantly when more than one layer is present. With the help of the high performance computers at Oak Ridge National Lab, the NC State team discovered both good and bad news about graphene: With a single layer of graphene, the mobility — and therefore conductivity — shown by the researchers’ simulations turned out to be much higher than they had originally thought; the bad news is that the mobility of electrons in bilayer graphene is roughly an order of magnitude lower than in a single graphene sheet.

Jell-O device detects organ failure

Using only aluminum foil, gelatin, a 12-cent LED light, and a few other inexpensive materials, researchers have developed a sensor that can detect pancreatitis quickly and easily. About the size of a matchbox, the sensor relies on a two-step process to diagnose the disease, a sudden inflammation of the pancreas that can lead to severe stomach pain, nausea, fever, shock and, in some cases, death.

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So many materials stories, so little time:

Cornell study: Graphene grains make atomic patchwork quilts

Dynamically tunable hemispherical electronic eye camera system with adjustable zoom capability

Eyeglasses that use liquid crystals to avoid the problems of bifocals

Sharp announces high-efficiency LED device for lighting purposes

Swiss and Colombian researchers develop electromagnetic wave tool to remotely detonate IEDs

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Because several ACerS members are directly or indirectly involved with LED research and development, and because I am doing some remodeling at my house, I figured that now would be a good time to investigate what reasonable LED options are available for residential lighting. I was even willing to fork over some extra cash for the inevitable premium price being charged for home LEDs, as long as the performance was good. Unfortunately, my experience was disappointing.

Obviously, LEDs are starting to make inroads in niche residential applications such as exterior holiday lights. But I wanted something more typical and useful from my perspective: A replacement for a 65-75 watt incandescent in a ceiling recessed-can fixture. Typically, these fixtures use “floodlight” type bulb. I limited my shopping to big box outlets, lighting stores and local hardware stores. (I did peak at Amazon and eBay to see what might be available, and the choices/prices/shipping hassles didn’t seem to justify taking that route.)

I ended up selecting what was described as an 18-watt indoor floodlight for about $40. When I screwed it in, the light was, uh, overwhelming. I felt like I was suddenly in one of those movie scenes where the detectives are interrogating a suspect under the glare of a single bright lamp. It certainly was bright, but only in an annoyingly focused small area. It made me think that instead of “floodlight,” the manufacturer meant spotlight.

Actually, I wasn’t totally surprised. It seems the difficulties of diffusing LED light is a known problem that has been a limiting factor with widespread LED adoption. I just hadn’t realized how huge of a problem it is for consumers and manufacturers.

But apropos to all this, and totally by coincidence, I came across this recent announcement from Panasonic touting that its new LED bulbs and lamps illuminate much larger areas. One of the products looks like a bulb; the other is a squarish, flattish ceiling lamp.

I am not sure I understand Panasonic’s approach, so I am going to rely on the description provided by Nikkei Monozukri’s Masaru Yoshida. Regarding the “Everleds” bulb (concept illustrated above), Yoshida says Panasonic gets around the narrow light distribution angles this way:

“[The] light source (LED package) is arranged in a circular shape inside a globe (a semi-spherical cover) and two light reflectors with apertural areas are used. The light from the LED package is reflected on the first light reflector to the back direction (normally to the side of the ceiling). And part of the light passing through the apertural area is reflected on the second reflector to the side. The light traveling in a straight line is diffused by the semi-spherical globe. As a result, it becomes possible to realize a light distribution angle as wide as that of an incandescent light bulb. […] Panasonic took measures to improve heat radiation. It arranged the circuit of the light bulb so that driver chips and other heat-sensitive components are located near the center of the circularly-arranged LED package, where temperature is relatively low.

The ceiling lamp’s operation is different and requires two LED modules. Again from Yoshida:

“One is mainly used to directly light the entire room by emitting light downwards (direct light module). And the other lights the ceiling and walls (indirect light module). […] Specifically, the LED module for direct light is placed in the four sides of the quadrangular ceiling light with its light-emitting area facing the inside. And light is emitted downwards from the module by using the reflector and the light diffuser located below the reflector. On the other hand, the LED module for indirect light is placed on the LED module for direct light, facing outward, so that light spreads horizontally. In addition, each module is equipped with two types of LED packages: a daylight-color LED package and an incandescent-color LED package.

For an Everled bulb equivalent to a 60-watt incandescent, the estimated price is around $45. The ceiling lamp (below) initially might sell for $600 (yikes!) Neither appear to be available in the U.S. market yet, but are likely to arrive sometime in the next 12 months.

As for now, I am returning my LED bulb and plan on waiting another year before I try again.

Credit: Panasonic

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