Articles from February 2017



Hydrogen Electric Car: New Storage System

Lawrence Livermore scientists have collaborated with an interdisciplinary team of researchers, including colleagues from Sandia National Laboratories, to develop an efficient hydrogen storage system that could be a boon for hydrogen-powered vehicles.

hydrogen lithiumHydrogenation forms a mixture of lithium amide and hydride (light blue) as an outer shell around a lithium nitride particle (dark blue) nanoconfined in carbon

Hydrogen is an excellent energy carrier, but the development of lightweight solid-state materials for compact, low-pressure storage is a huge challenge. Complex metal hydrides are a promising class of hydrogen storage materials, but their viability is usually limited by slow hydrogen uptake and release. Nanoconfinementinfiltrating the metal hydride within a matrix of another material such as carbon — can, in certain instances, help make this process faster by shortening diffusion pathways for hydrogen or by changing the thermodynamic stability of the material.

However, the Livermore-Sandia team, in conjunction with collaborators from Mahidol University in Thailand and the National Institute of Standards and Technology, showed that nanoconfinement can have another, potentially more important consequence. They found that the presence of internal “nano-interfaces” within nanoconfined hydrides can alter which phases appear when the material is cycled.

The key is to get rid of the undesirable intermediate phases, which slow down the material’s performance as they are formed or consumed. If you can do that, then the storage capacity kinetics dramatically improve and the thermodynamic requirements to achieve full recharge become far more reasonable,” said Brandon Wood, an LLNL materials scientist and lead author of the paper. “In this material, the nano-interfaces do just that, as long as the nanoconfined particles are small enough. It’s really a new paradigm for hydrogen storage, since it means that the reactions can be changed by engineering internal microstructures.”

The research is reported  in the journal Advanced Materials Interfaces

Source: https://www.llnl.gov/

Nano Printing Heralds NanoComputers Era

A new technique using liquid metals to create integrated circuits that are just atoms thick could lead to the next big advance for electronics. The process opens the way for the production of large wafers around 1.5 nanometres in depth (a sheet of paper, by comparison, is 100,000nm thick). Other techniques have proven unreliable in terms of quality, difficult to scale up and function only at very high temperatures – 550 degrees or more.

Professor Kourosh Kalantar-zadeh, from RMIT’s School of Engineering in Australia , led the project with  colleagues from RMIT and researchers from CSIRO, Monash University, North Carolina State University and the the University of California, He observed that the electronics industry had “hit a barrier.

nano printing

The fundamental technology of car engines has not progressed since 1920 and now the same is happening to electronics. Mobile phones and computers are no more powerful than five years ago. That is why this new 2D printing technique is so important – creating many layers of incredibly thin electronic chips on the same surface dramatically increases processing power and reduces costsIt will allow for the next revolution in electronics.

Benjamin Carey, a researcher with RMIT and the CSIRO, said creating electronic wafers just atoms thick could overcome the limitations of current chip production. It could also produce materials that were extremely bendable, paving the way for flexible electronics. “However, none of the current technologies are able to create homogenous surfaces of atomically thin semiconductors on large surface areas that are useful for the industrial scale fabrication of chips.  Our solution is to use the metals gallium and indium, which have a low melting point.  These metals produce an atomically thin layer of oxide on their surface that naturally protects them. It is this thin oxide which we use in our fabrication method,”  explains Carey.

By rolling the liquid metal, the oxide layer can be transferred on to an electronic wafer, which is then sulphurised. The surface of the wafer can be pre-treated to form individual transistors.  We have used this novel method to create transistors and photo-detectors of very high gain and very high fabrication reliability in large scale,” he adds.

The paper outlining the new technique has been published in the journal Nature Communications.

Source: http://www.rmit.edu.au/

Wooden SkyScrapers

High-rise wooden buildings, such as 14-storey apartment building “The Tree” in Norway, are altering city skylines in what the timber industry is heralding as a new era that will dent the supremacy of concrete and steel.

wooden skyscraper

CLICK ON THE IMAGE TO ENJOY THE VIDEO

Situated on the Bergen waterfront, The Tree is the tallest wooden building in the world. The 52.8 metre high structure is one of a growing number of so-called Plyscrapers altering city skylines. The timber industry say it’s an environmental solution, as countries seek to reduce emissions.

It will never totally displace concrete and steel, but it’s definitely a part in our solution towards our struggle towards a CO2 neutral society,”  says Ole Herman Kleppe, Chief Project Manager.

The architects insist that fears of fire in such timber homes are groundless.  “These columns and these CLT panels they don’t burn. They’re so thick that they don’t burn. In addition, they are painted with fire resistant paint and the house is sprinkled so we have all possible ways to prevent a fire in the house. So actually, this is the safest house in Bergen regarding fire.” explains Kleppe.

The 14-storey structure is made of sustainable wood. But concrete makers dispute the idea that timber is greener, insisting that deforestation causes more CO2 emissions. The Tree’s structure isn’t entirely wooden.

It’s concrete on this roof because it adds weight and it was necessary to add weight to this wooden building because it kind of dampens the swinging,” adds Per Reigstad, architect at Artec.

Later this year a wooden building that’s two inches taller will open in Vancouver. Even taller structures are being planned in Vienna and London.

Source: http://www.reuters.com/

Car Pollution: Nanoparticles Travel Directly From The Nose To The Brain

The closer a person lives to a source of pollution, like a traffic dense highway, the more likely they are to develop Alzheimer’s or dementia, according to a study by the University of Southern California (USC) that has linked a close connection to pollution and the diseases. In a mobile lab, located just off of one of Los Angeles’ busiest freeways, USC scientists used a state-of-the-art pollution particle collector capable of gathering nano-sized particulate matter.

car pollution

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We have shown that, as you would expect, the closer you get to the sources of these particles in our case the freeways, the higher the concentrations. So there is an exponential decay with distance. That means basically that, the concentration of where we are right now and if we were, let’s just say 20 or 10 or 50 yards from the freeway, those levels would be probably 10 times higher than where we are right now,” says Costas Sioutas, USC Professor of Environmental Engineering.

That means proximity to high concentrations of fossil fuel pollution, like a congested freeway, could be hazardous. Particulate matter roughly 30 times thinner than the width of a human hair, called PM2.5, is inhaled and can travel directly through the nose into the brain. Once there, the particles cause inflammatory responses and can result in the buildup of a type of plaque, which is thought to further the progression of Alzheimer’s. “Our study brought in this new evidence and I would say probably so far the most convincing evidence that the particle may increase the risk of dementia. This is really a public health problem. And I think the policy makers need to be aware of that, the public health risk associated with high level of PM2.5,” explains Jiu-Chiuan Chen, Associate Professor of Preventive Medicine.

USC researchers analyzed the data of more than 3,500 women who had the APOE4 gene, the major known risk-factor gene for Alzheimer’s disease. It showed that, over the course of a decade, the women who lived in a location with high levels of the PM2.5 pollution were 92 percent more likely to develop dementia.

Source: https://news.usc.edu/
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http://www.reuters.com/

Scalable Production of Conductive Graphene Inks

Conductive inks based on graphene and layered materials are key for low-cost manufacturing of flexible electronics, novel energy solutions, composites and coatings. A new method for liquid-phase exfoliation of graphite paves the way for scalable production.

Conductive inks are useful for a range of applications, including printed and flexible electronics such as radio frequency identification (RFID) antennas, transistors or photovoltaic cells. The advent of the internet of things is predicted to lead to new connectivity within everyday objects, including in food packaging. Thus, there is a clear need for cheap and efficient production of electronic devices, using stable, conductive and non-toxic components. These inks can also be used to create novel composites, coatings and energy storage devices.

A new method for producing high quality conductive graphene inks with high concentrations has been developed by researchers working at the Cambridge Graphene Centre at the University of Cambridge, UK. The novel method uses ultrahigh shear forces in a microfluidisation process to exfoliate graphene flakes from graphite. The process converts 100% of the starting graphite material into usable flakes for conductive inks, avoiding the need for centrifugation and reducing the time taken to produce a usable ink. The research, published in ACS Nano, also describes optimisation of the inks for different printing applications, as well as giving detailed insights into the fluid dynamics of graphite exfoliation.

graphene scalable production

“This important conceptual advance will significantly help innovation and industrialization. The fact that the process is already licensed and commercialized indicates how it is feasible to cut the time from lab to market” , said Prof. Andrea Ferrari, Director of the Cambridge Graphene Centre.

Source: http://www.graphene.cam.ac.uk/

Drones Re-Charging Wireless While Airborne

Scientists have demonstrated a highly efficient method for wirelessly transferring power to a drone while it is flying. The breakthrough could in theory allow flying drones to stay airborne indefinitely by simply hovering over a ground support vehicle to recharge opening up new potential industrial applications.

The technology uses inductive coupling, a concept initially demonstrated by inventor Nikola Tesla over 100 years ago. Two copper coils are tuned into one another, using electronics, which enables the wireless exchange of power at a certain frequency. Scientists have been experimenting with this technology for decades, but have not been able to wirelessly power flying technology.

prodrone

Now, scientists from Imperial College London (ICL) have removed the battery from an off-the-shelf mini-drone and demonstrated that they can wirelessly transfer power to it via inductive coupling. They believe their demonstration is the first to show how this wireless charging method can be efficiently done with a flying object like a drone, potentially paving the way for wider use of the technology.

To demonstrate their approach the researchers bought an off-the-shelf quadcopter drone, around 12 centimetres in diameter, and altered its electronics and removed its battery. They made a copper foil ring, which is a receiving antennae that encircles the drone’s casing. On the ground, a transmitter device made out of a circuit board is connected to electronics and a power source, creating a magnetic field.

The drone’s electronics are tuned or calibrated at the frequency of the magnetic field. When it flies into the magnetic field an alternating current (AC) voltage is induced in the receiving antenna and the drone’s electronics convert it efficiently into a direct current (DC) voltage to power it.

Source: http://www3.imperial.ac.uk/

Wireless Power

A new method developed by Disney Research for wirelessly transmitting power throughout a room enables users to charge electronic devices as seamlessly as they now connect to WiFi hotspots, eliminating the need for electrical cords or charging cradles. The researchers demonstrated their method, called quasistatic cavity resonance (QSCR), inside a specially built 16-by-16-foot room at their lab. They safely generated near-field standing magnetic waves that filled the interior of the room, making it possible to power several cellphones, fans and lights simultaneously.

wirelesspowe

This new innovative method will make it possible for electrical power to become as ubiquitous as WiFi,” said Alanson Sample, associate lab director & principal research scientist at Disney Research. “This in turn could enable new applications for robots and other small mobile devices by eliminating the need to replace batteries and wires for charging.

In this work, we’ve demonstrated room-scale wireless power, but there’s no reason we couldn’t scale this down to the size of a toy chest or up to the size of a warehouse,” said Sample, who leads the lab’s Wireless Systems Group.

According to Sample, is a long-standing technological dream. Celebrated inventor Nikola Tesla famously demonstrated a wireless lighting system in the 1890s and proposed a system for transmitting power long distances to homes and factories, though it never came to fruition. Today, most wireless power transmission occurs over very short distances, typically involving charging stands or pads.

The QSCR method involves inducing electrical currents in the metalized walls, floor and ceiling of a room, which in turn generate uniform magnetic fields that permeate the room’s interior. This enables power to be transmitted efficiently to receiving coils that operate at the same resonant frequency as the magnetic fields. The induced currents in the structure are channeled through discrete capacitors, which isolate potentially harmful electrical fields.

Our simulations show we can transmit 1.9 kilowatts of power while meeting federal safety guidelines,” Chabalko said. “This is equivalent to simultaneously charging 320 smart phones.”

A research report on QSCR by the Disney Research team of Matthew J. Chabalko, Mohsen Shahmohammadi and Alanson P. Sample was published in the online journal PLOS ONE.

Source: https://phys.org/

Printable solar cells

A University of Toronto (U of T) Engineering innovation could make building printing cells as easy and inexpensive as printing a newspaper. Dr. Hairen Tan and his team have cleared a critical manufacturing hurdle in the development of a relatively new class of solar devices called perovskite solar cells. This alternative solar technology could lead to low-cost, printable solar panels capable of turning nearly any surface into a power generator.

Printable Perovskite SolarCell

Economies of scale have greatly reduced the cost of silicon manufacturing,” says University Professor Ted Sargent (ECE), an expert in emerging solar technologies and the Canada Research Chair in Nanotechnology and senior author on the paper. “Perovskite solar cells can enable us to use techniques already established in the printing industry to produce solar cells at very low cost. Potentially, perovskites and silicon cells can be married to improve efficiency further, but only with advances in low-temperature processes.”

Today, virtually all commercial solar cells are made from thin slices of crystalline silicon which must be processed to a very high purity. It’s an energy-intensive process, requiring temperatures higher than 1,000 degrees Celsius and large amounts of hazardous solvents.

In contrast, perovskite solar cells depend on a layer of tiny crystals — each about 1,000 times smaller than the width of a human hair — made of low-cost, light-sensitive materials. Because the perovskite raw materials can be mixed into a liquid to form a kind of ‘solar ink’, they could be printed onto glass, plastic or other materials using a simple inkjet process.

Source: http://news.engineering.utoronto.ca

How To Fine-Tune NanoFabrication

Daniel Packwood, Junior Associate Professor at Kyoto University’s Institute for Integrated Cell-Material Sciences (iCeMS), is improving methods for constructing tiny “nanomaterials” using a “bottom-up” approach called “molecular self-assembly”. Using this method, molecules are chosen according to their ability to spontaneously interact and combine to form shapes with specific functions. In the future, this method may be used to produce tiny wires with diameters 1/100,000th that of a piece of hair, or tiny electrical circuits that can fit on the tip of a needle.

nanofabrication

Molecular self-assembly is a spontaneous process that cannot be controlled directly by laboratory equipment, so it must be controlled indirectly. This is done by carefully choosing the direction of the intermolecular interactions, known as “chemical control”, and carefully choosing the temperature at which these interactions happen, known as “entropic control”. Researchers know that when entropic control is very weak, for example, molecules are under chemical control and assemble in the direction of the free sites available for molecule-to-molecule interaction. On the other hand, self-assembly does not occur when entropic control is much stronger than the chemical control, and the molecules remain randomly dispersed.

Packwood teamed up with colleagues in Japan and the U.S. to develop a computational method that allows them to simulate molecular self-assembly on metal surfaces while separating the effects of chemical and entropic controls. This new computational method makes use of artificial intelligence to simulate how molecules behave when placed on a metal surface. Specifically, a “machine learning” technique is used to analyse a database of intermolecular interactions. This machine learning technique builds a model that encodes the information contained in the database, and in turn this model can predict the outcome of the molecular self-assembly process with high accuracy.

Source: http://www.kyoto-u.ac.jp/

Nano-LED 1000 Times More Efficient

The electronic data connections within and between microchips are increasingly becoming a bottleneck in the exponential growth of data traffic worldwide. Optical connections are the obvious successors but optical data transmission requires an adequate nanoscale light source, and this has been lacking. Scientists at Eindhoven University of Technology (TU/e) now have created a light source that has the right characteristics: a nano-LED that is 1000 times more efficient than its predecessors, and is capable of handling gigabits per second data speeds.

NANO LEDWith electrical cables reaching their limits, optical connections like fiberglass are increasingly becoming the standard for data traffic. Over longer distances almost all data transmission is optical. Within computer systems and microchips, too, the growth of data traffic is exponential, but that traffic is still electronic, and this is increasingly becoming a bottleneck. Since these connections (‘interconnects’) account for the majority of the energy consumed by chips, many scientists around the world are working on enabling optical (photonic) interconnects. Crucial to this is the light source that converts the data into light signals which must be small enough to fit into the microscopic structures of microchips. At the same time, the output capacity and efficiency have to be good. Especially the efficiency is a challenge, as small light sources, powered by nano– or microwatts, have always performed very inefficiently to date.
The researchers in Eindhoven believe that their nano-LED is a viable solution that will take the brake off the growth of data traffic on chips. However, they are cautious about the prospects. The development is not yet at the stage where it can be exploited by the industry and the production technology that is needed still has to get off the ground.
The findings are reported in the online journal Nature Communications.

Source: https://www.tue.nl/

Killing Cancer Cells From Inside

Researchers have witnessed – for the first time – cancer cells being targeted and destroyed from the inside, by an organo-metal compound discovered by the University of Warwick (UK). Professor Peter J. Sadler, and his group in the Department of Chemistry, have demonstrated that Organo-Osmium FY26 – which was first discovered at Warwick – kills cancer cells by locating and attacking their weakest part.

osmium compound fy26 in cancer cell
This is the first time that an Osmium-based compound – which is fifty times more active than the current cancer drug cisplatin – has been seen to target the disease. Using the European Synchrotron Radiation Facility (ESRF), researchers analysed the effects of Organo-Osmium FY26 in ovarian cancer cells – detecting emissions of X-ray fluorescent light to track the activity of the compound inside the cells

Looking at sections of cancer cells under nano-focus, it was possible to see an unprecedented level of minute detail. Organelles like mitochondria, which are the ‘powerhouses’ of cells and generate their energy, were detectable. In cancer cells, there are errors and mutations in the DNA of mitochondria, making them very weak and susceptible to attack.

FY26 was found to have positioned itself in the mitochondriaattacking and destroying the vital functions of cancer cells from within, at their weakest point. Researchers were also able to see natural metals which are produced by the body – such as zinc and calcium – moving around the cells. Calcium in particular is known to affect the function of cells, and it is thought that this naturally-produced metal helps FY26 to achieve an optimal position for attacking cancer.

Source: http://www2.warwick.ac.uk

Mental Viagra

As Valentines Day approaches, love may be in the air…. but it’s also in the mind. Scientists in London say a natural hormone – appropriately named kisspeptinenhances brain regions associated with sex and love. In placebo-controlled trials, 29 healthy young men were injected with kisspeptin and their brains scanned using MRI.

couple in loveCLICK ON THE IMAGE TO ENJOY THE VIDEO

During the MRI they performed tasks designed to activate certain areas of the brain. So we used tasks to activate the sexual arousal centres of the brain and task to activate the romance sensors of the brain using images. And we observed that kisspeptin boosted the activity in sexual arousal and romantic circuits in the brain,” says Dr. Alexander Comninos, Endocrinologist at Imperial College  London.

Kisspeptin is found in all men and women, and is vital for stimulating puberty. “So there’s a link, not just with the hormones, but also the stimulation of reproductive hormones but also stimulating how we perceive sexual images in the brain, and that’s what the really exciting part of this study been; is how for the first time having a link between a hormone that’s stimulating reproductive hormones, but also how our brains perceive sexual images,” explains Waljit Dhillo, Professor in Endocrinology at Imperial College London .

Psychological sexual disorders can make it difficult for couples to conceive. Biological factors play a large part, but the role of the brain and emotion can’t be overlooked. A kisspeptin-based therapy could be an answer, say researchers. It differs from drugs like Viagra, which only trigger a physiological response. “Viagra is very different. So Viagra will cause vasodilation, it will make the vessels essentially dilate, blood will go down to the genital area. So it’s a completely different action, it’s mechanical if you like. Whereas this is much more psychological in terms of its altering how we perceive sexual images in our brains. So it’s a completely different mechanism of action“, adds Professor Dhillo.

More research is needed – including on women and then eventually in patients with psychological issues. Kisspeptin could one day help treat sexual disorders of the mind… in effect, mental Viagra.

Source: http://www.reuters.com/