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Archive for the ‘materials’ category: Page 293

Sep 17, 2015

Making 3-D objects disappear: Researchers create ultrathin invisibility cloak

Posted by in categories: engineering, materials, nanotechnology

Invisibility cloaks are a staple of science fiction and fantasy, from Star Trek to Harry Potter, but don’t exist in real life, or do they? Scientists at the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley have devised an ultra-thin invisibility “skin” cloak that can conform to the shape of an object and conceal it from detection with visible light. Although this cloak is only microscopic in size, the principles behind the technology should enable it to be scaled-up to conceal macroscopic items as well.

Working with brick-like blocks of gold nanoantennas, the Berkeley researchers fashioned a “skin cloak” barely 80 nanometers in thickness, that was wrapped around a three-dimensional object about the size of a few biological cells and arbitrarily shaped with multiple bumps and dents. The surface of the skin cloak was meta-engineered to reroute reflected waves so that the object was rendered invisible to optical detection when the cloak is activated.

“This is the first time a 3D object of arbitrary shape has been cloaked from ,” said Xiang Zhang, director of Berkeley Lab’s Materials Sciences Division and a world authority on metamaterials — artificial nanostructures engineered with electromagnetic properties not found in nature. “Our ultra-thin cloak now looks like a coat. It is easy to design and implement, and is potentially scalable for hiding macroscopic objects.”

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Sep 16, 2015

New Solar Panels That Work At Night

Posted by in categories: materials, nanotechnology, solar power, sustainability

Nighttime solar panels, night solar panels, night photovoltaics, Solar cells, solar power at night, idaho national laboratory, solar technology, solar film, nanotechnology solar, nanoantennas, New Solar Panels Can Harvest Energy After Dark

Despite the enormous untapped potential of solar energy, one thing is for sure- photovoltaics are only as good as the sun’s rays shining upon them. However, researchers at the Idaho National Laboratory are close to the production of a super-thin solar film that would be cost-effective, imprinted on flexible materials, and would be able to harvest solar energy even after sunset!

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Sep 16, 2015

Filling a void in stem cell therapy

Posted by in categories: biotech/medical, life extension, materials

Stem cells coming along nicely, Stanford demonstrate how creating artificial stem cell niches improve grafting and regeneration of bone and it should have a broad application for other tissues. Properly developed we could regenerate organs and tissues by injecting enough stem cells in these manufactured protective niches.

One could potentially take it a stage further and modify the stem cells with genes of interest to make them more robust. Ex-vivo cell manipulation is also considerably cheaper than in-vivo therapy.


New porous hydrogel could boost success of some stem cell-based tissue regeneration, researchers say.

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Sep 16, 2015

Scientists Have Created a System That Absorbs 99.7% of All Sound

Posted by in category: materials

Is this thing on? That’s likely what Hong Kong University of Science and Technology scientists thought, shortly after they’d developed a new system that absorbs 99.7 percent of all the sound that hits it.

Many systems use sonic insulators to deaden sound: materials which absorb sound, typically over a small range of frequencies. By combining different insulators into a composite, it’s possible to absorb a large range of sounds — but it’s difficult to create such a material that absorbs all the the frequencies. It would just be too big and complex. That means that there’s a limit to the amount of sound they can absorb.

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Sep 16, 2015

Researchers model graphene/nanotube hybrids to test properties

Posted by in categories: electronics, materials

Rice University researchers discovered that putting nanotube pillars between sheets of graphene could create hybrid structures with a unique balance of strength, toughness and ductility throughout all three dimensions.

Carbon nanomaterials are common now as flat sheets, nanotubes and spheres, and they’re being eyed for use as building blocks in hybrid structures with unique for electronics, heat transport and strength. The Rice team is laying a theoretical foundation for such structures by analyzing how the blocks’ junctions influence the properties of the desired materials.

Rice materials scientist Rouzbeh Shahsavari and alumnus Navid Sakhavand calculated how various links, particularly between carbon nanotubes and graphene, would affect the final hybrid’s properties in all directions. They found that introducing junctions would add extra flexibility while maintaining almost the same strength when compared with materials made of layered graphene.

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Sep 15, 2015

Nanoscale Solar Cells Outperform Traditional Technology

Posted by in categories: computing, information science, materials, nanotechnology, solar power, sustainability

Scientists have designed a novel type of nanoscale solar cell. Initial studies and computer modelling predict these cells will outperform traditional solar panels, reach power conversion levels by over 40 percent.

Solar power cells work through the conversion of sunlight into electricity using photovoltaics. Here solar energy is converted into direct current. A photovoltaic system uses several solar panels; with each panel composed of a number of solar cells. This combines to create a system for the supply usable solar power.

To investigate what is possible in terms of solar power, the researchers have examined the Shockley-Queisser limit for different materials. This equation describes the maximum solar energy conversion efficiency achievable for a particular material, allowing different materials to be compared as candidates for power generation.

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Sep 12, 2015

Ras Labs Is Testing Futuristic Muscle Material That Could Make Robots Feel More Human

Posted by in categories: biotech/medical, cyborgs, materials, robotics/AI, space

Synthetics startup Ras Labs is working with the International Space Station to test “smart materials” that contract like living tissue. These “electroactive” materials can expand, contract and conform to our limbs just like human muscles when a current moves through them – and they could be used to make robots move and feel more human to the touch.

Ras Labs co-founder Lenore Rasmussen accidentally stumbled upon the synthetic muscle material years ago while mixing chemicals in the lab at Virginia Tech. The experiment turned out to be with the wrong amount of ingredients, but it produced a blob of wobbly jelly that Rasmussen noticed contracted and expanded like muscles when she applied an electrical current.

It would be years later when Rasmussen’s cousin nearly lost his foot in a farming accident that she would start to employ that discovery to robotic limbs and space travel. The co-founder thought her cousin might lose his foot and started researching prosthetics.

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Sep 12, 2015

How curly nanowires can absorb more light to power nanoscale electronic circuits

Posted by in categories: electronics, energy, materials, nanotechnology, solar power, sustainability

This illustration shows a prototype device comprising bare nanospring photodetectors placed on a glass substrate, with metal contacts to collect charges (credit: Tural Khudiyev and Mehmet Bayindir/Applied Optics)

Researchers from Bilkent University, Ankara, Turkey, have shown that twisting straight nanowires into springs can increase the amount of light the wires absorb by up to 23 percent. Absorbing more light is important because one application of nanowires is turning light into electricity, for example, to power tiny sensors instead of requiring batteries.

If nanowires are made from a semiconductor like silicon, light striking the wire will dislodge electrons from the crystal lattice, leaving positively charged “holes” behind. Both the electrons and the holes move through the material to generate electricity. The more light the wire absorbs; the more electricity it generates. (A device that converts light into electricity can function as either a solar cell or a photosensor.)

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Sep 8, 2015

Lipid DNA origami may lead to advanced future nanomachines

Posted by in categories: biotech/medical, materials, nanotechnology

Using a double layer of lipids facilitates assembly of DNA origami nanostructures, bringing us one step closer to future DNA nanomachines, as in this artist’s impression (credit: Kyoto University’s Institute for Integrated Cell-Material Sciences)

Kyoto University scientists in Japan have developed a method for creating larger 2-D self-assembling DNA origami nanostructures.

Current DNA origami methods can create extremely small two- and three-dimensional shapes that could be used as construction material to build nanodevices, such as nanomotors, in the future for targeted drug delivery inside the body, for example. KurzweilAI recently covered advanced methods developed by Brookhaven National Laboratory and Arizona State University’s Biodesign Institute.

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Sep 8, 2015

Nanotubes open new path toward quantum information technologies

Posted by in categories: computing, materials, nanotechnology, quantum physics, security

“Beyond implementation of quantum communication technologies, nanotube-based single photon sources could enable transformative quantum technologies including ultra-sensitive absorption measurements, sub-diffraction imaging, and linear quantum computing. The material has potential for photonic, plasmonic, optoelectronic, and quantum information science applications…”


In optical communication, critical information ranging from a credit card number to national security data is transmitted in streams of laser pulses. However, the information transmitted in this manner can be stolen by splitting out a few photons (the quantum of light) of the laser pulse. This type of eavesdropping could be prevented by encoding bits of information on quantum mechanical states (e.g. polarization state) of single photons. The ability to generate single photons on demand holds the key to realization of such a communication scheme.

By demonstrating that incorporation of pristine into a silicon dioxide (SiO2) matrix could lead to creation of solitary oxygen dopant state capable of fluctuation-free, room-temperature single , Los Alamos researchers revealed a new path toward on-demand single photon generation. Nature Nanotechnology published their findings.

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