Nanocrystals make dentures shine

The hardest substance in the human body is moved by its strongest muscles: When we heartily bite into an apple or a hotdog, enormous strengths are working on the surface of our teeth.

"What the natural tooth enamel has to endure also goes for dentures, inlays or bridges," glass chemist Prof. Dr. Christian Rüssel of the Friedrich Schiller University Jena (Germany) says. After all, these are worn as much as healthy teeth. Ceramic materials used so far are not very suitable for bridges, as their strengths are mostly not high enough. Now Prof. Rüssel and his colleagues of the Otto-Schott-Institute for Glass Chemistry succeeded in producing a new kind of glass ceramic with a nanocrystalline structure, which seems to be well suited to be used in dentistry due to their high strength and its optical characteristics. The glass chemists of Jena University recently published their research results in the online-edition of the science magazine Journal of Biomedical Materials Research.

Glass-ceramics on the basis of magnesium-, aluminium-, and silicon oxide are distinguished by their enormous strength. "We achieve a strength five times higher than with comparable denture ceramics available today," Prof. Rüssel explains. The Jena glass chemists have been working for a while on high density ceramics, but so far only for utilisation in other fields, for instance as the basis of new efficient computer hard drives. "In combination with new optical characteristics an additional field of application is opening up for these materials in dentistry," Prof. Rüssel is convinced.

Materials, to be considered as dentures are not supposed to be optically different from natural teeth. At the same time not only the right colour shade is important. "The enamel is partly translucent, which the ceramic is also supposed to be," Prof. Rüssel says.

To achieve these characteristics, the glass ceramics are produced according to an exactly specified temperature scheme: First of all the basic materials are melted at about 1.500 °C, then cooled down and finely cut up. Then the glass is melted again and cooled down again. Finally, nanocrystals are generated by controlled heating to about 1,000 °C. "This procedure determines the crystallisation crucial for the strength of the product," the glass chemist Rüssel explains. But this was a technical tightrope walk. Because a too strongly crystallised material disperses the light, becomes opaque and looks like plaster. The secret of the Jena glass ceramic lies in its consistence of nanocrystals. The size of these is at most 100 nanometers in general. "They are too small to strongly disperse light and therefore the ceramic looks translucent, like a natural tooth," Prof. Rüssel says.

A lot of developing work is necessary until the materials from the Jena Otto-Schott-Institute will be able to be used as dentures. But the groundwork is done. Prof. Rüssel is sure of it.

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The above story is reprinted from materials provided by Friedrich Schiller University Jena, via AlphaGalileo.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

Journal Reference:

Marc Dittmer, Christian Rüssel. Colorless and high strength MgO/Al2O3/SiO2 glass-ceramic dental material using zirconia as nucleating agent. Journal of Biomedical Materials Research Part B: Applied Biomaterials, 2012; 100B (2): 463 DOI: 10.1002/jbm.b.31972

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Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Battelle-R&D Magazine Annual Global Funding Forecast Predicts R&D Spending Growth Will Continue While Globalization Accelerates

The Battelle-R&D Magazine annual Global R&D Funding Forecast shows global research and development (R&D) spending is expected to grow by about 5.2 percent in 2012 to more than $1.4 trillion.

One of the most remarkable findings of the report is that R&D funding growth will largely be driven by Asian economies-a number projected to increase by nearly 9 percent in 2012. Elsewhere in the world, growth remains strong and stable in the aftermath of the global recession. Greece is the only country among the world's top 40 R&D spenders that is not expected to increase its R&D budget during the next year. The closely watched study also predicts that overall European R&D will grow by about 3.5 percent while North American R&D will grow by 2.8 percent.  

Experts from Battelle and R&D Magazine forecast that a 2.1 percent growth in United States R&D expenditures will be balanced against an estimated 2 percent inflation rate, suggesting that U.S. R&D investments will remain flat in real terms over the next year. That $436 billion in forecasted spending is expected to be broken down in the following way:

U.S. Private Industry will spend by far the largest amount with a projection of $279.6 billion in R&D in 2012, up 3.75 percent over 2011.U.S. Federal Government spending will reach $125.6 billion in 2012, a decrease of 1.16 percent.Academia in the U.S. will spend $12 billion on research in 2012, up 2.85 percent over last year.Non-profits will increase spending in 2012 by 2.7 percent to $14.5 billion and other government entities in the U.S. will round out total R&D expenditures by increasing 2.72 percent to $3.8 billion.

Another notable trend the Funding Forecast reveals is the increased expectation that R&D investments will provide financial returns and positive commercial outcomes. Several years ago, only 10 percent of U.S. industries calculated return on investment (ROI) from R&D efforts, while data from a survey that is part of the Funding Forecast now indicates that 40 percent measure that figure.

"The pharmaceutical industry illustrates this trend best as it faces increased scrutiny of R&D spending versus limited productivity and weak pipelines for blockbuster drugs," said Martin Grueber, Battelle Research Leader and co-author of the report. "However, industry isn't the only sector under the ROI microscope. There also are increasing demands that public sector R&D investments show real economic and policy outcomes."

With 18 U.S. corporations among the top 50 firms ranked by R&D spending, the U.S. remains dominant in manufacturing R&D. However, translating this level of R&D and innovation into output, products and jobs is a challenge faced by both U.S. corporations and government. There is wide agreement that technology collaborations are important to growth with many manufacturers planning on increasing collaborative activity such as knowledge sharing, shorter development cycles and the availability of proprietary technologies.

Survey respondents identified the top three ways government could help support manufacturing R&D as: providing tax credits to companies with active R&D programs, supporting academic R&D in manufacturing and increasing tech transfer support from U.S. national labs to industry.

Energy: Energy-related research sponsored by U.S. manufacturers and technology providers will reach nearly $6.7 billion in 2012, up 23.1 percent from 2011. Global spending by energy-related companies will grow by 7.8 percent to reach $17.9 billion in 2012.

A review panel commissioned by the U.S. Department of Energy (DOE) identified key R&D areas where DOE program and investment can play a significant development role, including several in which the DOE historically has underinvested. The areas address both energy supply and demand and relate to both stationary power (deploying clean electricity, modernizing the grid and increasing building/industrial efficiency) and transport power (deploying alternative hydrocarbon fuels, electrifying the vehicle fleet, and increasing vehicle efficiency.)

The panel calls on DOE to maintain a mix of analytic, assessment and fundamental engineering research capabilities in a broad set of energy-technology areas while seeking to balance more assured activities against higher-risk transformational work. At the same time, the report acknowledges that the efforts must be relevant to the private sector. There is a tension between supporting work that industry doesn't-the long term nature of basic research-and the urgency of the nation's energy challenge.

Life Science: United States R&D spending in the life science industry is expected to decline by 5.7 percent to $73.2 billion in 2012 as pharmaceutical firms tighten their R&D budgets. Global R&D spending in the industry also is forecast to decline by 2.2 percent to $147.3 billion.

This sector includes such diverse firms as multi-national pharmaceutical corporations, large medical device and instrument companies and both large and small biotechnology firms.

A major change in the funding and performing of life science R&D is the convergence in public and private sector R&D toward open innovation and open source information-especially in areas needing considerable fundamental research. It is due, in part, to the pharmaceutical industry's retrenchment from its conventional model to a more reduced internal R&D function and focuses more on collaboration and ROI. The ripple effects of impending patent expirations and the widely reported decline in productivity in the development and approval of significant new medicines are driving the strategic changes.

Chemicals and Materials: R&D in the broadly defined chemicals and materials industry is expected to grow by 11.4 percent in the U.S. to $9.3 billion in 2012, while growing by 3.8 percent globally to $33.8 billion.

Nanotechnology and its applications continue to pervade all industrial applications with biomedical applications beginning during the past two years. More than 15 U.S. government agencies propose funding $2.13 billion in nanotechnology research including DOE at $611 million, the National Institutes of Health at $465 million, the National Science Foundation at $456 million and the Department of Defense at $368 million.

An emerging priority in advanced materials is a heightened focus on developing alternative sources or processes related to rare earth metals because of China's recent export limits on supplies. In the industrial sector around the world, closed non-Chinese rare earth mines are being re-opened; however, the environmental requirements for operating these mines have increased since they closed, making additional R&D and capital expenditures necessary to develop new and improved processing programs.

Particle-free silver ink prints small, high-performance electronics

 University of Illinois materials scientists have developed a new reactive silver ink for printing high-performance electronics on ubiquitous, low-cost materials such as flexible plastic, paper or fabric substrates.

Jennifer Lewis, the Hans Thurnauer Professor of Materials Science and Engineering, and graduate student S. Brett Walker described the new ink in the Journal of the American Chemical Society.

"We are really excited about the wide applicability and excellent electrical properties of this new silver ink," said Lewis, the director of the Frederick Seitz Materials Research Laboratory at the U. of I.

Electronics printed on low-cost, flexible materials hold promise for antennas, batteries, sensors, solar energy, wearable devices and more. Most conductive inks rely on tiny metal particles suspended in the ink. The new ink is a transparent solution of silver acetate and ammonia. The silver remains dissolved in the solution until it is printed, and the liquid evaporates, yielding conductive features.

"It dries and reacts quickly, which allows us to immediately deposit silver as we print," Walker said.

The reactive ink has several advantages over particle-based inks. It is much faster to make: A batch takes minutes to mix, according to Walker, whereas particle-based inks take several hours and multiple steps to prepare. The ink also is stable for several weeks.

The reactive silver ink also can print through 100-nanometer nozzles, an order of magnitude smaller than particle-based inks, an important feature for printed microelectronics. Moreover, the ink's low viscosity makes it suitable for inkjet printing, direct ink writing or airbrush spraying over large, conformal areas.

"For printed electronics applications, you need to be able to store the ink for several months because silver is expensive," Walker said. "Since silver particles don't actually form until the ink exits the nozzle and the ammonia evaporates, our ink remains stable for very long periods. For fine-scale nozzle printing, that's a rarity."

The reactive silver ink boasts yet one more key advantage: a low processing temperature. Metallic inks typically need to be heated to achieve bulk conductivity through a process called annealing. The annealing temperatures for many particle-based inks are too high for many inexpensive plastics or paper. By contrast, the reactive silver ink exhibits an electrical conductivity approaching that of pure silver upon annealing at 90 degrees Celsius.

"We are now focused on patterning large-area transparent conductive surfaces using this reactive ink," said Lewis, who also is affiliated with the

Beckman Institute for Advanced Science and Technology, the Micro and Nanotechnology Lab and the department of chemical and biomolecular engineering at the U. of I.

The U.S. Department of Energy and the National Science Foundation supported this work.

Story Source:

The above story is reprinted from materials provided by University of Illinois at Urbana-Champaign.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

Journal Reference:

S. Brett Walker, Jennifer A. Lewis. Reactive Silver Inks for Patterning High-Conductivity Features at Mild Temperatures. Journal of the American Chemical Society, 2012; 120105082029000 DOI: 10.1021/ja209267c

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

Agilent Technologies Completes Acquisition of BioSystem Development Business

01-03-2012: Agilent Technologies Inc. announced it has completed the acquisition of the BioSystem Development business. BioSystem Development is a privately held company that develops and manufactures the AssayMAP Microchromatography platform to meet the analytical needs of the life sciences industry. Financial details of the transaction were not disclosed.

As life science discovery and development continues to move toward a better understanding of biological responses to disease, and has an increased emphasis on protein-based therapeutics by pharmaceutical companies, the need for automated, quality protein sample preparation and analysis has become critical.

BioSystem Development’s AssayMAP platform, based on disposable microchromatography cartridges, enables for the first time, automation of complex, multi-step sample preparation workflows. These include protein purification, characterization and analysis solutions for bioprocess development, biomarker identification and analysis, as well as a variety of other life science research applications.

The acquisition formalizes and streamlines the ongoing collaboration between BioSystem Development and Agilent to combine AssayMAP technology with Agilent's industry-leading automated liquid handling platforms, to reduce discovery and development time and increase lab efficiency.

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