The new OSRAM Ostar Stage LEDs for bright spotlighting with color mixing.

Here is what we are hearing:

MesoCoat hits milestone - cladding inside diameter of pipe

Abakan Inc. is pleased to announce that its subsidiary, MesoCoat Inc., has successfully completed a major milestone by cladding the inside diameter of steel pipe with corrosion and wear resistant alloys and expects to complete qualification with several oil majors within the next six months. Metal cladding for wear and corrosion protection is a $3.8 billion global market of which approximately 50% is for coating steel pipes which are used in the oil and gas, oil sands, mining and processing industries. The cladding of steel pipe is expected to double over the next four years because almost all of the new oil and gas fields being developed today are highly corrosive.

Brookfield now has available online: full recording of the live teleseminar with autocoats expert Lori Boggs

If you were not able to listen to Brookfield’s live teleseminar with Lori Boggs last month, you can catch up on everything that you missed by visiting the ViscosityJournal.com now. The interview is available, in its entirety, for your listening pleasure. During the interview, Boggs reviews “Autocoats: Which Viscosity Test Method Should Be Used.” Testing the viscosity of coatings in the automotive world requires a range of devices and instruments, ranging from Zahn Cups to Stormer Viscometers and Cone/Plate Rheometers. Boggs explains which one should you use and why. She also answers whether or not you can get by with a single instrument to do it all. Boggs is an experienced veteran in the autocoats business at BASF.

3M licenses dental ceramic coloring technology to Zirkonzahn GmbH

3M announced that Zirkonzahn GmbH has become the latest dental company to license 3M’s patented technology that enables the coloring of zirconia-based dental restorations. This technology improves esthetics for patients by enabling the color matching of dental restorations to the natural color of the patients’ teeth. Since 3M’s development and launch of this game-changing technology, much of the industry colors dental zirconia using this process.

Morgan Thermal Ceramic’s Superwool high temperature felt and millboard for industrial appliances

Morgan Thermal Ceramics has available Superwool HT Felt and Superwool HT Millboard, ideal for fabricating gaskets and heat shields for industrial appliances, including ovens, fryers and cooking equipment. The lightweight, multipurpose products are available in a full range of sizes, thicknesses and densities and offer equivalent performance to traditional refractory ceramic fiber insulation in many applications. Superwool fiber was developed to provide the improved high temperature characteristics required to be an alternative to RCF. Superwool fiber products feature low bio-persistence and felt and millboard made from Superwool fiber are fully exonerated from any carcinogenic classification under nota Q of directive 97/69 EC issued by the European Union. They are not restricted by European REACH regulations.

New high-purity metals and materials catalog available

Alfa Aesar, a Johnson Matthey Company, has published a new High-purity Metals and Materials Catalog that highlights Alfa Aesar’s entire range of metals and alloys from aluminum to zirconium, featuring purities up to 99.9999%. Products are offered in a broad variety of forms, including wires, foils, slugs, targets, powders, thermocouple wires and many more. In addition to the pure metals and elements section, the new 340-page catalog includes sections on metal gauzes, carbon/graphite, ceramics, evaporation materials, nanomaterials, brazing products, fuel cell catalysts, optics and crystals, labware and equipment and more. To request a free copy of the catalog, contact Alfa Aesar at 800-343-0660 or email.

Small power packs for a big impression: New OSRAM Ostar Stage LEDs with a flat glass window

With their much flatter profile, the new OSRAM Ostar Stage LEDs provide the basis for compact spotlights with an extremely narrow beam and high luminance. These LEDs are ideal for moveable stage lights, known as moving heads, which provide powerful light beams for rock concerts and other impressive lighting arrangements. Instead of the usual lens, OSRAM Ostar Stage LEDs have a flat glass cover with an anti-reflective coating, giving the LED a much flatter profile. It is now only 1.23-mm high — one quarter of the usual height. Spotlights can therefore be made much more compact.
The glass cover on the new LEDs has been optimized for injecting the light into lens systems. Its etendue (the emission angle/area ratio of the emitting light surface to the projected light surface) in conjunction with customer optics enables a very narrow beam of light (+/- 9°) to be produced. This beam is smaller (by a factor of 2) than spotlights based on plastic-encapsulated LEDs. This optimum bundling of the light increases the luminance of the spotlight also by a factor of 2.

LM Wind Power’s 73.5 meter blades flying on the largest offshore wind turbine in the world

LM Wind Power’s 73.5-meter blades became the first 70+-meter blades to be installed when Alstom inaugurated the largest offshore wind turbine in the world on Mar. 19, 2012, at Carnet in the Loire-Atlantique region of France. The composite structures have been developed specifically for Alstom’s Haliade 150-6 MW wind turbine in a close collaboration between the two companies to boost energy capture while keeping loads down. The innovative blade design has already been through several rounds of testing before being installed on the turbine in France. LM Wind Power’s technology enables it to design and manufacture relatively lighter glass fiber and polyester blades for the length, but above all, LM Wind Power has proven ability to handle the industrialization of these blades, which is not easy. Alstom’s turbine has been EDF-EN/Dong Energy’s choice developed in response to a call for tenders launched by the French government that aims to install 3 GW of wind turbine power off French shores by 2015. Depending on the results of the tenders to be announced in April, Alstom and LM Wind Power plan to establish a blade manufacturing facility in Cherbourg with the capacity to produce up to 100 sets of 73.5-meter blades a year. Production is planned to start in 2016.

Lippert offers new type of modularized plaster-mold dryer

With deference to the ceramic industry’s need to conserve energy, drying specialist Lippert has designed an high performance, energy-efficient economical plaster-mold dryer. Thanks to the dryer’s high airflow velocities and relatively low process temperatures, the resultant modest differential between the plaster-mold temperature and the process temperature rewards the user with a very good thermal profile and accordingly gentle, stress-free drying. At the same time, the new approach sensationally shortens the accustomed drying times and lowers energy consumption to match. The modular, fully preassembled dryer can be installed by the customer’s own personnel. Even the electrical installation is easy, because the system is fully hard-wired to plug-in status. All the customer needs Lippert’s help for is the dryer’s commissioning.

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Mario Affatigato from Coe College identified the interaction between glass and living matter as a grand challenge that can be addressed by the glass and ceramics research community. Credit: ACerS.

What are the next “grand challenges” for ceramic materials research? What emerging research areas should the ceramic materials research community make its priority? What are the big questions that ceramic materials can answer?

Those are the questions that a workshop taking place this week is working on answering. Greg Rohrer, professor at Carnegie Mellon University, organized the workshop to tap into the collective eyes-and-ears of about 40 scientists from academia, industry and government labs. The workshop is supported by a National Science Foundation grant.

According to Rohrer, the last such workshop was in 1997, so it’s been awhile since the ceramic research community undertook a systematic self-evaluation. “There are new tools and capabilities, especially in microscopy and computers. It’s a new landscape, and our research needs to reflect that,” Rohrer said in his introductory remarks.

Established in 1950, NSF’s mission is to “initiate and support basic scientific research and research fundamental to the engineering process, and to initiate and support programs to strengthen scientific and engineering research potential.” Other agencies, like DOE and the military research offices, also support ceramic materials research, but always in the context of their mission applications. Free from the constraints of mission-based applications, the NSF is in a unique position to provide a framework for this kind of exercise.

Rohrer says, “As researchers working on ceramics, we need to be able to say, ‘This is why ceramics research is relevant, and these are the important scientific challenges that the ceramics research community intends to address in the next five to ten years.’”

Rohrer set out three goals for participants (paraphrased):

• Identify 6-8 scientific grand challenges with a five- to ten-year horizon,
• Consider the status U.S. ceramic research in a global context,
• Comment on effectiveness of NSF funding mechanisms.

Yesterday and this morning are “set-up” days. Participants have been giving short talks about their work and identifying the grand challenges they see. Rohrer organized the talks into four materials categories: glasses, non-oxide ceramics, composites and oxide ceramics. After each grouping, panel discussions help the group hone in on common themes across the materials groups and bring focus to the unique challenges facing each group.

The hard work begins later today. Each group will draft summary reports based on what they heard and discussed, and this afternoon’s talks will mix in the international and NSF pieces. Tomorrow the four committees will build-out their draft summary reports and present them to the group. These reports will be the basis for a full report including references, images, etc. that will be published in the Journal of the American Ceramic Society in late 2012. Also, Rohrer will be presenting the report at ICC4 meeting in Chicago this July in a track on Emerging Topics in Ceramics Research.

What themes have emerged so far? Yesterday I heard a lot of interesting ideas about surfaces and interfaces, including some new ways of thinking about them. Nanoscale effects on properties and processing, nanoscale characterization and computational methods also were mentioned frequently. It will be interesting to see how the four committees interpret what they heard and what they collectively tease out as Grand Challenges.

Rohrer emphasized that this exercise is intended to be inclusive and welcomes input from others engaged in ceramic research. “I know there are people who should be here, but participation had to be limited. I’m interested in collecting as many ideas as possible,” he said. Rohrer’s contact details are available at his website.

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Check ‘em out:

Ultrafast large-amplitude relocation of electronic charge in ionic crystals (pdf)

(PNAS, Early Edition) We have demonstrated an ultrafast relocation of charge that is induced by electronic excitation and steered by coherent low-frequency motions of the ionic crystal lattice. Our results reveal the nonequilibrium charge dynamics in ionic materials on their intrinsic length and time scales. Such insight is relevant for a large range of polar materials and their ultrafast dynamic response. In principle, low-frequency lattice motions can be controlled by interaction with tailored optical pulses. Our results suggest that such schemes allow for an ultrafast all-optical control of electric polarization in potassium dihydrgen phosphate and related ionic materials.

New production process could cut solar cell prices by half

(Gizmag) In Twin Creeks Technologies’ proprietary Hyperion process, three-millimeter-thick disks of crystalline silicon are placed in a vacuum chamber, where they’re bombarded with a beam of hydrogen ions. The ion accelerator that’s used is reportedly ten times more powerful than anything else commercially available. Through control of the voltage of its beam, a layer of ions is precisely deposited on each disk. Those ions proceed to penetrate the silicon, so they’re located just below its surface. The disks are then robotically transferred to a furnace and heated. This causes the ions to expand into microscopic bubbles of hydrogen gas, which in turn causes a 20-micrometer-thick layer of silicon to peel off the surface of each disk. A supportive metal backing is then applied to that layer, and it’s ready for use.

Metamaterials may advance with new femtosecond laser technique

Researchers in Harvard’s School of Engineering and Applied Sciences have cleared an important hurdle in the development of advanced materials, called metamaterials, that bend light in unusual ways. Working at a scale applicable to infrared light, the Harvard team has used extremely short and powerful laser pulses to create three-dimensional patterns of tiny silver dots within a material. Those suspended metal dots are essential for building futuristic devices like invisibility cloaks. The new fabrication process, described in the journal Applied Physics Letters, advances nanoscale metal lithography into three dimensions-and does it at a resolution high enough to be practical for metamaterials.

Origami-inspired paper sensor could test for malaria and HIV for less than 10 cents; sensors can be printed out on an office printer and take less than a minute to assemble

Inspired by the paper-folding art of origami, chemists at the University of Texas at Austin have developed a 3D paper sensor that may be able to test for diseases such as malaria and HIV for less than 10 cents a pop. Such low-cost, “point-of-care” sensors could be incredibly useful in the developing world, where the resources often don’t exist to pay for lab-based tests, and where, even if the money is available, the infrastructure often doesn’t exist to transport biological samples to the lab. A hydrophobic material, such as wax or photoresist, is laid down into tiny canyons on chromatography paper. It channels the sample that’s being tested — urine, blood, or saliva, for instance — to spots on the paper where test reagents have been embedded.

Reemerging superconductivity at 48 K in iron chalcogenides

(Nature) Pressure has an essential role in the production1 and control of superconductivity in iron-based superconductors. Substitution of a large cation by a smaller rare-earth ion to simulate the pressure effect has raised the superconducting transition temperature T_c to a record high of 55 K in these materials. In the same way as T_c exhibits a bell-shaped curve of dependence on chemical doping, pressure-tuned T_c typically drops monotonically after passing the optimal pressure. Here we report that in the superconducting iron chalcogenides, a second superconducting phase suddenly reemerges above 11.5 GPa, after the T_c drops from the first maximum of 32 K at 1 GPa. The T_c of the reemerging superconducting phase is considerably higher than the first maximum, reaching 48.0-48.7 K for Tl_0.6Rb_0.4Fe_1.67Se₂, K_0.8Fe_1.7Se₂ and K_0.8Fe_1.78Se₂.

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Ptychography is a new approach to microscopy that eschews lenses. Instead, diffraction patterns are collected and reconstructed using algorithms that work backwards to create the image. In this example, the image on the left is a visible light diffraction pattern of a lily anther. The raw data is reconstructed into the image on the right. Credit: Rodenburg; University of Sheffield.

When we were learning about Fourier transformations in my college linear algebra class, the instructor wrote a big matrix on the board, pointed to it and said, “That’s a lens.” I remember being surprised at seeing something I’d always thought of as having to be tangible expressed as a mathematical abstraction.

What if you could go the other way? That is, what if mathematics were applied to diffracted electron beams and reconstructed into images instead of applying lenses to electron beams on their way to the specimen?

That is the approach taken by a group led by John Rodenburg from the University of Sheffield (U.K.). They may be on the verge of revolutionizing the field of high-resolution microscopy by, basically, using mathematics to construct images from diffraction patterns, eliminating the need for optics and their limitations. In a recent paper in Nature Communications, the authors explain, “Here we demonstrate a form of diffractive imaging that unshackles the image formation process from the constraints of electron optics, improving resolution over that of the lens used by a factor of five …”

They say the method, called electron ptychography, “has no fundamental experimental boundaries: further development of this proof-of-principle could revolutionize sub-atomic scale transmission imaging.” The best resolution possible in a fully optimized SEM set-up would be about 1.2 nanometers, they say in the paper. Resolutions of about 0.24 nanometers (atomic scale) are achievable with ptychography.

In a press release from the university, Rodenburg explains how the image is constructed.

We measure diffraction patterns rather than images. What we record is equivalent to the strength of the electron, X-ray or light waves which have been scattered by the object - this is called their intensity. However, to make an image, we need to know when the peaks and troughs of the waves arrive at the detector - this is called their phase.

The key breakthrough has been to develop a way to calculate the phase of the waves from their intensity alone. Once we have this, we can work out backwards what the waves were scattered from: that is, we can form an aberration-free image of the object, which is much better than can be achieved with a normal lens.

Although the paper describes the method for electron microscopy, ptychography can be applied to microscopy using other illumination sources including visible light, producing images such as those above. This would be advantageous in the biological sciences. Without lenses closing in on them, cells can be observed without disruption, for example.

The method is still in its proof-of-concept stage. The paper presents images of gold particles to demonstrate the capability of the method, but it is expected to be applicable to ceramic materials, too. In an email, Rodenburg said the group had not looked at any ceramic specimens yet, “However, it is certainly true to say that electron imaging is key for the study of ceramics, so certainly as we (and, hopefully, others) adopt and improve the approach it will have significant impact in the study of ceramics.”

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Lost vibrations: In the insulating state, the VO₂ crystal structure vibrates at four well-defined frequencies when hit by a low power laser pulse. These vibrations modulate the reflectivity over time as shown in the left image. In the right image, the power of the laser has been turned up and the VO₂ has stopped vibrating, indicating that the phase transition has occurred. Credit: Fritz Haber Institute.

We received word that an international team of researchers has developed a way to use an ultrafast optical system to track phase transitions in materials that occur in time spans that may be as short as trillionths of a second. The laser-based system provides a “table-top” alternative to more complicated X-ray-based systems for investigating phase transistions

Working under grants from NSF and the Alexander von Humboldt Foundation, investigators at Vanderbilt University and the Fritz Haber Institute of the Max Planck Society (Germany) decided to focus on the phase transitions of vanadium dioxide, which undergoes some phase transitions so rapidly that they, so far, have been tough to follow. For example, in a paper published in Nature Communications, the authors say that the shift between the transparent and reflective phases in VO₂ is the fastest phase transition known.

“This means that there is a lot that we still don’t know about the dynamics of these critical processes,” says professor of physics Richard Haglund in a Vanderbilt news release. Haglund directed the team of researchers from Vanderbilt.

The group wanted to explore how it is that VO₂ can shift from a transparent, semiconducting phase to a reflective, metallic phase extremely quickly. This phase change can be induced by heating the material above 150°F, and it is this property that has made VO₂ an attractive material for thermochromic windows. VO₂ can also be forced to undergo the phase transition by hitting it with a pulse of light from a laser, and thus it is also a candidate material for optical switches and faster computer memory.

Haglund has wondered for many years about how and why VO₂ achieves this rapid transition. Back in 2005, he directed a study, the results of which were published in Optics Letters, in which he noted, “Phase transitions in solids generally occur at the speed of sound in the material, but vanadium dioxide makes the switch 10 times faster. So far no one has succeeded in coming up with a definitive explanation for that rapid a change.”

In this most recent work, Hagland’s group at Vandy created and characterized the VO₂ thin films. The VO₂ film was then given to the FHI group, who used an adaptation of the “pump-and-probe” method using a femtosecond infrared laser. Their method can simultaneously launch a phase change and optically track the progress of the phase change by measuring the reflectivity of the surface of the material.

“With this new technique, we were able to see a lot of details that we’ve never seen before,” said Haglund. He says they learned that the electrons in the material rearrange themselves first, followed by a movement of the atoms as the material shifts from its semiconductor to metallic-phase orientation. According to the group’s paper, these insights into VO₂ can be used to design high-speed optical switches

“The real power of this technique is that it is sensitive to atomic changes inside the material which are usually observed using expensive large-scale X-ray sources. Now we can do the experiment optically and in the lab on a tabletop,” says Simon Wall, an Alexander von Humbolt fellow at the Fritz Haber Institute..

The Nature Communications paper is titled, “Ultrafast changes in lattice symmetry probed by coherent phonons” (doi:10.1038/ncomms1719).

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