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According to an ORNL press release, by adapting conventional glass fiber drawing technology to process carbon nanotubes into multichannel assemblies, researchers believe they have the potential to mimic the human nervous system.

“Our goal is to use our discovery to mimic nature’s design using artificial sensors to effectively restore a person’s ability to sense objects and temperatures,” says Ilia Ivanov, a researcher in the Center for Nanophase Materials Sciences Division.

The ultimate goal is to duplicate the function of a living system by combining the existing technology of glass fiber drawing with the multifunctionality of submicron (0.4 micron) scale carbon nanotubes, according to Ivanov, who described the process.

“We make this material in a way similar to what you may have done in high school when making a glass capillary over a Bunsen burner,” Ivanovsays . “There, you would take the glass tube, heat it up and pull, or draw, as soon as the glass became soft.”

Ivanov and John Simpson of the Measurement Science and Systems Engineering Division are doing something similar except they use thousands of glass tubes filled with carbon nanotube powder. After several draw cycles, they demonstrated that they could make fibers just four times thicker than a human hair containing 19,600 submicron channels with each channel filled with conducting carbon. Each carbon nanotube-containing channel is electrically insulated from its neighbors by glass so it can be used as an individual communication channel.

This multichannel composite has many other potential uses, including in aeronautics and space applications, where low weight of conducting wires is important. The next steps are to make these channels highly conductive and then show sensor communication through individual channels.

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Caltech researchers, led by Harry Atwater, have engineered a type of metamaterial that allows it to bend light in part of the visible spectrum from nearly any angle toward an optimal direction. They report that this artificial optical material can handle light with any polarization over a broad range of incident angles, making it the first negative-index metamaterial to operate at visible frequencies.

So what? Atwater explains, in a Caltech release, that, “By engineering a metamaterial with such properties, we are opening the door to such unusual – but potentially useful – phenomena as superlensing (high-resolution imaging past the diffraction limit), invisibility cloaking and the synthesis of materials index-matched to air, for potential enhancement of light collection in solar cells,” he says.

I know from his previous work that Atwater is interested in maximizing the efficiency of solar cells. Recently I did a post on his team’s creation of a 3D photovoltaic array composed of a bed silicon wires given an antireflective coating intermixed with light-scattering particles to surpass convention light absorption techniques. Thus, it appears that Atwater’s group has worked out two methods to improve PV efficiency: increase the amount of light that gets to a PV system, and increase the amount of that light that then gets converted.

A number of other groups are working with metamaterials to achieve negative refractive indexes. The Caltech researchers, however, are using a different and somewhat simpler approach. They only need a single layer of silver permeated with coupled surface plasmonic waveguide elements.

The plasmonic waveguide elements route these coupled waves through the material.

One researcher, grad student Stanley Burgos, says the material can be tuned to respond to a different wavelength of light coming from nearly any angle with any polarization by changing the material or adjusting the geometry of the waveguides. “By carefully engineering the coupling between such waveguide elements, it was possible to develop a material with a nearly isotopic refractive index tuned to operate at visible frequencies,” explains Burgos.

“The fact that our [negative index metamaterial] design is tunable means we could potentially tune its index response to better match the solar spectrum, allowing for the development of broadband wide-angle metamaterials that could enhance light collection in solar cells,” says Atwater. “It means that it can ‘accept’ light from a broad range of angles. In the case of solar cells, this means more light collection and less reflected or ‘wasted’ light.”

A paper on the team’s work has been published in Nature Materials.

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Who would pass up the opportunity to win a solar-powered robot, hydro clocks and hydrogen powered remote control cars? Apparently, YOU!

Don’t miss this fun opportunity to share your experience on how materials are impacting the environment. Post your comments to this Earth Day post for a chance to win.

Comments will be accepted through tomorrow, Thursday, April 29, so don’t miss out on the fun!

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ACerS Fellow Prashant Kumta has been a pioneer in the use of nanoceramic materials for bone regeneration and to bind and transport proteins and protein-like substances into cells. Kumta, who teaches at both Carnegie Mellon University and the University of Pittsburgh’s Schools of Engineering and Dental Medicine, discusses how his interest in bioglass and bioceramics coincided with the explosion of nanotechology, opening up new opportunities for biocompatible materials that could be slowly absorbed by the body.

9 minutes.

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In celebration of Earth day, the DOE announced today that it will invest over $200 million to the development of solar and water power technologies.

“Expanding the U.S. clean-energy manufacturing base is an important part of the Administration’s goals to diversify electricity supply options, increase national security, and accelerate green jobs development,” says Secretary Steven Chu. “These investments will help strengthen American competitiveness in renewable energy and transform the U.S. into a lasting manufacturing presence in the 21st century clean-energy economy.”

• Photovoltaic Manufacturing Initiative – up to $125 million over five years. Funding will be available for applicants in two topic areas:  University-Focused Development and Industry-Focused Development. This funding opportunity requires that each applicant organization submit a concept paper in addition to standard application materials. Concept papers are due June 3, 2010, with full applications due in early August.

• Photovoltaic Supply Chain Development – up to $40 million over three years. The DOE is seeking projects focused on component and manufacturing technologies that show a strong potential to impact a substantial segment of the photovoltaic industry within two to five years.  Examples include engineering lower cost coating materials, electrical components to improve performance, processes that reduce manufacturing waste, or equipment that dramatically improves manufacturing or installation speed. The Department plans to select both large and small companies that can quickly develop new photovoltaic supply chain solutions. The Department anticipates that approximately $10-$15 million annually will be available to fund these PV supply chain projects. Applications are due July 2, 2010.

• National Administrator of the Solar Instructor Training Network – up to $4.5 million over five years. This funding opportunity will select a National Administrator that will act as a central coordinating body for the Training Network. The National Administrator will manage the collaboration of the Training Network members, disseminating their products and conducting other outreach efforts such as providing recommendations for the adoption of best practices. Applications are due June 15, 2010.  
  

For more information on these Funding Opportunity Announcements, please visit the Solar Energy Technologies Program’s Financial Opportunities.

The water power funding opportunity includes the following:

• Marine and Hydrokinetic Technologies – up to $39 million over four years. This funding opportunity seeks to leverage private-sector investment in MHK technologies by providing cost-shared funding to industry and industry-led partnerships in order to advance the technological and operational readiness of MHK systems and components. The goal is to effectively transition leading MHK system and component designs toward commercialization. Applications are due June 7, 2010.

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