background preloader

New Materials

Facebook Twitter

Atomic Trampoline. Physicists observe 'negative mass' Image copyright SCIENCE PHOTO LIBRARY Physicists have created a fluid with "negative mass", which accelerates backwards when pushed. In the everyday world, when an object is pushed, it accelerates in the same direction as the force applied to it; this relationship is described by Isaac Newton's Second Law of Motion. But in theory, matter can have negative mass in the same sense that an electric charge can be positive or negative. The phenomenon is described in Physical Review Letters journal. Prof Peter Engels, from Washington State University (WSU), and colleagues cooled rubidium atoms to just above the temperature of absolute zero (close to -273C), creating what's known as a Bose-Einstein condensate.

In this state, particles move extremely slowly, and following behaviour predicted by quantum mechanics, acting like waves. They also synchronise and move together in what's known as a superfluid, which flows without losing energy. He added: "It looks like the rubidium hits an invisible wall. " Exposing a sheet of thermochromic liquid crystals to a source of heat causes a local shift in its structure that produces a vivid change in color. Scientists have confirmed a brand new form of matter: time crystals. For months now, there's been speculation that researchers might have finally created time crystals - strange crystals that have an atomic structure that repeats not just in space, but in time, putting them in constant oscillation without energy.

Now it's official - researchers have just reported in detail how to make and measure these bizarre crystals. And two independent teams of scientists claim they've actually created time crystals in the lab based off this blueprint, confirming the existence of an entirely new phase of matter. The discovery might sound pretty abstract, but it heralds in a whole new era in physics - for decades we've been studying matter that's defined as being 'in equilibrium', such as metals and insulators. But it's been predicted that there are many more strange types of matter out there in the Universe that aren't in equilibrium that we haven't even begun to look into, including time crystals.

And now we know they're real. And it's not just speculation, either. Blood-repellent materials: A new approach to medical implants. Medical implants like stents, catheters and tubing introduce risk for blood clotting and infection – a perpetual problem for many patients. Colorado State University engineers offer a potential solution: A specially grown, “superhemophobic” titanium surface that’s extremely repellent to blood. The material could form the basis for surgical implants with lower risk of rejection by the body. Biomedical, materials approaches It’s an outside-the-box innovation achieved at the intersection of two disciplines: biomedical engineering and materials science. The work, recently published in Advanced Healthcare Materials, is a collaboration between the labs of Arun Kota, assistant professor of mechanical engineering and biomedical engineering; and Ketul Popat, associate professor in the same departments.

Kota, an expert in novel, “superomniphobic” materials that repel virtually any liquid, joined forces with Popat, an innovator in tissue engineering and bio-compatible materials. Paper bike helmet wins Dyson award. Image copyright Dyson A recyclable, folding cycling helmet made of paper has won this year's international James Dyson Award. The EcoHelmet is designed for people who use bike-sharing schemes and might not always have a helmet with them. Designer Isis Shiffer is delighted with the win but admits that a paper helmet may be a "tough sell".

She describes herself as an "ardent but slow" cyclist and came up with the idea when she was using bike-sharing schemes around the world. "When I was exploring new cities I had no access to a helmet and I didn't want to spend $30 buying one," she told the BBC. She decided to design one, made of cheap, recyclable materials that would cost less than $5. The helmet uses a honeycomb structure to protect the head which, according to Ms Shiffer, is "incredibly good at absorbing impact". The design was tested at Imperial College in London. "They have a test rig for helmets and the professor in charge of the lab let me test out a lot of materials. Tesla shows off solar roof tiles. Image copyright Reuters Roof tiles with built-in solar panels have been unveiled by Tesla chief executive Elon Musk. The tiles, made from glass, are intended to be a more attractive way to add solar panels to homes, compared with currently-used solar technology. The launch took place in Universal Studios, Los Angeles, on what used to be the set for the television show Desperate Housewives.

It comes with Tesla due to take over struggling energy firm Solar City. Some of the electric carmaker's investors have expressed concern over the takeover, suggesting it is a Tesla-funded bail-out of a company Mr Musk has a vested interest in as its biggest shareholder. Solar City’s chief executive is Mr Musk’s cousin. Bringing the solar tiles to the Desperate Housewives set was a way of displaying the idea’s key selling point: it looks far better than solar panelling.

Also part of the launch was Powerwall 2, Tesla’s home battery product. Tesla shareholders vote on the acquisition on 17th November. Silkworms Spin Super-Silk After Eating Carbon Nanotubes and Graphene. Materials programmed to shape shift. Scientists have pre-programmed materials to change their shape over time. Previous shape-shifting materials have needed some external trigger to tell them to transform, like light or heat.

Now, a US-based team has encoded a sequence of shape transformations into the very substance of a polymer, with each change occurring at a pre-determined time. Details appear in Nature Communications journal. The principles could be applied in implants that deliver medicine from within the human body and the technology could also see use in heavy industry. Professor Sergei Sheiko from the University of North Carolina at Chapel Hill, and colleagues introduced two types of chemical bond to their polymer: permanent bonds and dynamic (or reversible) bonds. The permanent bonds store the material's final shape, while the dynamic bonds control how quickly it can reach this shape.

Prof Sheiko said there were several parameters in the material which, when adjusted, allowed the scientists to control the changes. Vantablack, 'world's blackest material,' now comes in a spray. Let's all try to imagine what the blackest possible black might look like. Like Batman's suit? Like the unlit depths of a coal mine? Like swimming at the bottom of a cup of espresso? According to Surrey Nanosystems, it looks like Vantablack, a special coating the company describes as "the world's blackest material. " Sprayable Vantablack is known as Vantablack S-VIS.

There are those of us who would love to pop down to the local hardware store and buy a can of Vantablack spray, but that's not how it works. The wider availability of Vantablack is bound to spark some imaginations. Origami Footwear: Lightweight Lace-Free Shoes Wrap & Fit Any Feet. A Japanese designer and Italian shoemaker have taken a fresh approach to athletic footwear, adapting the minimalist art of cloth wrapping to form the basis of a flexible shoe that fits any foot shape. Masaya Hashimoto worked with Vibram, the makers of foot-shaped FiveFingers shoes (with articulated toes), to create the Furoshiki series of shoes with wrapping soles that fold around feet without needing laces (a simple hook and and loop system).

A specially-engineered gripping system keeps the shoes in place and make it possible for the shoe to perform like ordinary footwear but with less weight and material. The system has a number of advantages, including more flexible sizing than traditional shoes, easier packing for travel and the ability to skip socks comfortably. From Vibram: “The concept for this type of footwear was derived from the Japanese custom of packaging items by wrapping them in cloth fabric. New Compound Can Transform Infrared into Visible Light | Chemistry, Materials... A team of scientists in Germany has developed a compound that can transform infrared into warm, white-colored light. The new compound emits a broadband spectrum of light upon excitation with an infrared laser. Image credit: Nils Wilhelm Rosemann. The team, headed by Dr. Nils Wilhelm Rosemann of the Philipps-Universität Marburg, designed their compound of tin and sulfur, and with a diamondoid-like structure, then coating this scaffolding with organic ligands.

“The compound [(RdelocSn)4S6](Rdeloc=4–(CH2=CH)–C6H4) was obtained as a fine amorphous powder,” Dr. Rosemann and co-authors said. This compound is non-volatile, air-stable, and thermally stable up to 572 degrees Fahrenheit (300 degrees Celsius). “Inorganic nanocrystals form the core of this compound and are coated with organic ligands on the surface,” they explained. Flat lens promises possible revolution in optics. Image copyright Federico Capasso A flat lens made of paint whitener on a sliver of glass could revolutionise optics, according to its US inventors.

Just 2mm across and finer than a human hair, the tiny device can magnify nanoscale objects and gives a sharper focus than top-end microscope lenses. It is the latest example of the power of metamaterials, whose novel properties emerge from their structure. Shapes on the surface of this lens are smaller than the wavelength of light involved: a thousandth of a millimetre. "In my opinion, this technology will be game-changing," said Federico Capasso of Harvard University, the senior author of a report on the new lens which appears in the journal Science. The lens is quite unlike the curved disks of glass familiar from cameras and binoculars. Singly, each pillar interacts strongly with light. Computer calculations are needed to find the exact pattern which will replicate the focussing effect of a conventional lens. And with ease. Milestone in solar cell efficiency by UNSW engineers. A new solar cell configuration developed by engineers at the University of New South Wales has pushed sunlight-to-electricity conversion efficiency to 34.5% – establishing a new world record for unfocused sunlight and nudging closer to the theoretical limits for such a device.

The record was set by Dr Mark Keevers and Professor Martin Green, Senior Research Fellow and Director, respectively, of UNSW’s Australian Centre for Advanced Photovoltaics, using a 28-cm2 four-junction mini-module – embedded in a prism – that extracts the maximum energy from sunlight. It does this by splitting the incoming rays into four bands, using a hybrid four-junction receiver to squeeze even more electricity from each beam of sunlight. The new UNSW result, confirmed by the US National Renewable Energy Laboratory, is almost 44% better than the previous record – made by Alta Devices of the USA, which reached 24% efficiency, but over a larger surface area of 800-cm2.